COVID-19 Vaccines Affect Menstruation Reveals New Study

Authors: Acen Winnie August 8, 2022

Clinical studies on multiple COVID-19 vaccines have disregarded effects of vaccines on women’s menstruation.

There were countless complaints to doctors about related symptoms soon after immunizations were made available to the general population. Many women became aware of heavier-than-normal periods.

The authors of a recent survey on the subject that was published in the journal Science Advances wrote that, initially, some practitioners were dismissive. According to authors, “in media coverage, medical professionals and public health specialists raced to argue that there was ‘no biological mechanism’ or ‘no data’ to indicate a connection between vaccination delivery and menstruation abnormalities.”

Experts thus concluded that these changes were more likely the outcome of “stress“. However, such side effects are not unheard of, as irregular menstruation has occasionally been linked to typhoid, Hepatitis B, and HPV vaccines.

In April 2021, researchers began surveying vaccinated women to attain a better understanding of implications of the COVID-19 vaccine on menstruation. There were over 39,000 responses. Of these individuals who offered responses, 91 percent identified as women while the remaining nine percent were gender nonconforming.

Based on survey results, 44 percent of these individuals with regular menstruation cycles reported seeing no changes, while 41 percent reported an increase in their menstruation flow after having received the vaccination.

Amongst those with an irregular cycle, breakthrough bleeding was reported by: 71 percent of those using long-acting reversible contraceptives; 39 percent of those using gender-affirming hormones; and 66 percent of postmenopausal adults.

Study Based On Self Reported Experiences

A heavier flow after immunization was more likely to be reported by older adults, non-white or Hispanic/Latinx respondents, and those who experienced a fever or weariness after receiving the COVID-19 vaccine. Those with endometriosis, menorrhagia, or fibroids also reported heavier menstrual flows.

The study relied on self-reported experiences. Of course, such studies can be challenging; thus, it is too soon for researchers to draw any inferences about what findings might signify. Menstruating women, for instance, might have been more inclined to reply to the poll.

Researchers are unable to conclusively state that the vaccine was the source of these changes, or, if it was, how or why the vaccine might have affected menstrual cycles.

One theory is that menstrual changes may be the result of immune system reactions to the vaccine. According to the study, “generally, variations in menstrual bleeding are not unusual or harmful, but attention to these experiences is vital [in order] to develop confidence in medicine.”

In a press statement, co-author Katharine Lee, a professor of anthropology at Tulane University, stated, that “we anticipate that for most people,…changes related to COVID-19 vaccination are short-term. We recommend anyone who is concerned to contact their doctor for additional care.”

Experts maintain that obtaining the vaccine is one of the most reliable methods in avoiding severe COVID-19 related illness, which can lead to hospitalization, long-term COVID, and even death.

Doctors Criticize Fauci For Saying COVID Vaccines Induce ‘Only Temporary’ Menstrual Irregularities

Authors: Enrico Trigozo Epoch Times August 6, 2022

Dr. Anthony Fauci’s recent comments on menstrual irregularities met with serious rebuttal from gynecologists, who say COVID-19 vaccines should not have been injected into pregnant women without adequate safety testing.

Well, the menstrual thing is something that seems to be quite transient and temporary, that’s one of the points,” Fauci said in an appearance on Fox News on July 25, upon being asked about the effect of vaccines on menstrual cycles.

“We need to study it more,” Fauci added.

Fauci is the director of the National Institute of Allergy and Infectious Diseases (NIAID) and has been a frontman for COVID vaccine information in the United States.

Dr. Christiane Northrup MD, a former fellow in the American College of Obstetricians and Gynecologists, remarked to The Epoch Times on Fauci’s comments: “Unfortunately the menstrual problems we are seeing are far from transient and temporary. Many women have been bleeding daily or having heavy, irregular, painful periods for an entire year. And some of these are well past menopause. Something is way off here. ”

Dr. James Thorp is an extensively published 69-year-old physician MD board-certified in obstetrics and gynecology, as well as maternal-fetal medicine, who has been practicing obstetrics for over 42 years.

The significant and dramatic changes in menstrual patterns occurring after COVID-19 vaccines should not be marginalized. It is indicative of major adverse effects on women of reproductive age. The stakeholders claimed that the vaccine would remain at the injection site in the deltoid muscle. This was misinformation. The lipid nanoparticles (LNP’s) are now known to be distributed throughout the entire body and to be concentrated in the ovaries, according to at least two studies. Schadlich and colleagues demonstrated concentration of the LNP’s in ovaries of different mouse species and Wistar rats, in vivo, in vitro and by sophisticated microscopic imaging in 2012,” he told The Epoch Times.

A lipid nanoparticle is an extremely small particle, a fat-soluble membrane that is the cargo of the messenger RNA.

Pfizer’s Internal Documents

Pfizer’s internal documents, obtained via the Freedom of Information Act, show a 118-fold increase in the concentration of LNPs from the time of injection to 48 hours.

“The LNP’s are known to include toxic substances including polyethylene glycol and pseudo-uridinated mRNA. The limited number of ovum in the ovaries (about 1 million) are exposed to potentially toxic substances and could potentially have catastrophic effects on human reproduction,” Thorp said.  

The stakeholders claimed that the pseudo-uridinated mRNA could not be reverse transcribed into the human DNA. This was misinformation,” he added, referring to a Swedish study published in February 2022 that concluded that Pfizer’s COVID-19 vaccine is able to enter human liver cells and is converted into DNA.

Thorp and former Pfizer VP Michael Yeadon believe that the medical industrial complex had unequivocal evidence on the vaccine’s danger in pregnant women.

This is proven not only by VAERS but also by Pfizer’s own internal document ‘Pfizer 5.3.6 post-marketing experience” Thorp said.

Within the first 90 days of trials, there were 1,223 deaths, multiple severe adverse effects, and a 45 percent complication rate in pregnancy cases (274) that occurred in vaccinated mothers (124).

The 2012 study, mentioned by Thorp earlier, says that after testing with different mouse species and Wistar rats, “a high local accumulation of nanoparticles, nanocapsules and nanoemulsions in specific locations of the ovaries was found in all animals.”

Yeadon believes that the pharmaceutical industry “definitely knew,” since 2012, that the lipid nanoparticles would accumulate in the ovaries of women that took the vaccines.

“No one in the industry or in leading media could claim ‘they didn’t know about these risks to successful pregnancy,’” Yeadon told The Epoch Times in April.

Menstrual changes after Covid vaccines may be far more common than previously known

A study found that 42% of people with regular menstrual cycles said they bled more heavily than usual after their Covid vaccination.

Authors: Sarah Sloat NBC News July 15. 2022

When adults gained access to Covid vaccines last year, most knew to expect headaches, fatigue and soreness as side effects.

But some researchers think it’s time to add another common one to the list: temporary menstrual changes. 

An analysis published Friday in the journal Science Advances found that 42% of people with regular menstrual cycles said they bled more heavily than usual after vaccination. Meanwhile, 44% reported no change and around 14% reported a lighter period. Among nonmenstruating people — those post-menopause or who use certain long-term contraceptives, for example — the study suggests many experienced breakthrough or unexpected bleeding after their Covid shots.

The survey included over 39,000 people 18 to 80 years old who were fully vaccinated and had not contracted Covid. The study authors cautioned, though, that the percentages do not necessarily represent the rate of menstrual changes in the general population, since people who observed a difference were more likely to participate. The survey’s aim was simply to provide evidence for future studies, not to establish cause and effect. 

Still, other recent research also found that the Covid vaccine is associated with a small change in menstrual cycle length. 

The new survey started in April 2021, around the time people began to report unexpected bleeding and heavier flow post-vaccine. However, these anecdotes were at the time met with the rebuttal that there was no data linking menstrual changes to vaccination.  

That was both true and indicative of a larger problem. Individuals who took part in Covid vaccine trials were not asked if they experienced menstrual changes. 

“Before the vaccinations came out, I would say our knowledge on the subject of the connection between immunization and menstrual changes, in general, was nil,” said Candace Tingen, a program director with the gynecologic health and disease branch of the National Institute of Child Health and Human Development. Tingen was not involved in the recent survey.

Overall, few studies assess the direct effect of vaccination on the menstrual cycle, and most pharmaceutical trials have not included questions about changes to menstruation. 

Tingen views this as a mistake. Perhaps, she said, if Covid-19 vaccine trials had asked about menstruation, people would not have been surprised — or frightened — by this unexpected side effect. 

“It was really this lack of information that I think caused confusion, fear and perhaps vaccine hesitancy,” she said. 

Study co-author Katherine M.N. Lee said that overall, menstruation is understudied when it’s not relevant to pregnancy.

“It gets ignored because of the structure of science,” Lee, an assistant professor at Tulane University, said. “There are very few senior people in science and medicine who are not white men. It’s just not something they are thinking about as part of their lived experience.” 

Lee and her colleagues were inspired to ask people about their menstruation cycles after being vaccinated after seeing both friends and strangers online wonder why they experienced an unexpected change. 

The survey group included more than 3,500 people who identify as gender diverse. Approximately 84% of participants were white, and none were between the ages of 45 and 55 because the researchers didn’t want to include changes associated with perimenopause, when the body begins the transition to menopause. 

The respondents were vaccinated with Pfizer, Moderna, AstraZeneca, Johnson & Johnson and Novavax. 

COVID-19 Vaccination Considerations for Obstetric–Gynecologic Care

Last updated April 28, 2022

ACOG

This Practice Advisory was developed by the American College of Obstetricians and Gynecologists’ Immunization, Infectious Disease, and Public Health Preparedness Expert Work Group in collaboration with Laura E. Riley, MD; Richard Beigi, MD; Denise J. Jamieson, MD, MPH; Brenna L. Hughes, MD, MSc; Geeta Swamy, MD; Linda O’Neal Eckert, MD; Mark Turrentine, MD; and Sarah Carroll, MPH.

Summary of Updates

This Practice Advisory provides an overview of the currently available COVID-19 vaccines and guidance for their use in pregnant, recently pregnant, lactating, and nonpregnant individuals aged 12 years and older. For guidance and recommendations for the use of these vaccines in individuals aged 11 years or younger, please visit the website of the American Academy of Pediatrics. For additional information regarding severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and treatment, see ACOG’s Frequently Asked Questions.

This Practice Advisory has been updated to include the following:

  • Information regarding additional boosters for some individuals

Key Recommendations

  • The American College of Obstetricians and Gynecologists (ACOG) recommends that all eligible persons aged 12 years and older, including pregnant and lactating individuals, receive a COVID-19 vaccine or vaccine series.
  • The mRNA COVID-19 vaccines are preferred over the J&J/Janssen COVID-19 vaccine for all vaccine-eligible individuals, including pregnant and lactating individuals, for primary series, primary additional doses (for immunocompromised persons), and booster vaccination.
  • For patients who do not receive any COVID-19 vaccine, the discussion should be documented in the patient’s medical record. During subsequent office visits, obstetrician–gynecologists should address ongoing questions and concerns and offer vaccination again.
  • Obstetrician–gynecologists and other women’s health care practitioners should lead by example by being vaccinated and encouraging eligible patients to be vaccinated as well.
  • COVID-19 vaccines may be administered simultaneously with other vaccines. This includes vaccines routinely administered during pregnancy, such as influenza and Tdap.
  • Moderately to severely immunocompromised individuals (i.e., people who have undergone solid organ transplantation or have been diagnosed with conditions that are considered to have an equivalent level of immunocompromise) should receive an additional dose (i.e., an additional primary dose) of COVID-19 vaccine after their initial vaccine or vaccine series. The additional dose should be administered four weeks after the completion of the initial COVID-19 vaccine or vaccine series. For mRNA vaccines, this means immunocompromised individuals need a 3-dose primary series. For J&J/Janssen vaccine, immunocompromised individuals need a 2-dose primary series with the second dose being an mRNA vaccine.
  • All individuals aged 12 years and older who received an initial COVID-19 vaccine or vaccine series should receive a single booster dose of COVID-19 vaccine.
    • Individuals who received J&J/Janssen vaccine should receive a COVID-19 booster at least 2 months following their initial vaccine.
    • Individuals who received an mRNA vaccine should receive a booster at least 5 months following their initial vaccine series.
  • ACOG recommends that pregnant and recently pregnant people up to 6 weeks postpartum receive a booster dose of COVID-19 vaccine following the completion of their initial COVID-19 vaccine or vaccine series.
  • Individuals may receive any vaccine product available to them for their booster dose; they do not have to receive the same product as their initial vaccine or vaccine series; however:
    • The mRNA vaccines are preferred over the J&J/Janssen COVID-19 vaccine.
    • Adolescents aged 12–17 years are eligible for only the Pfizer-BioNTech COVID-19 vaccine.
  • Some individuals may choose to receive a second booster at least 4 months after their first booster depending on age, vaccine product received for their initial series and booster, or if they are immunocompromised. See Table 3 and CDC for details.
  • Pregnancy alone is not an indication for a second booster. However, pregnant patients who meet other criteria (age, vaccine product received for primary series and booster, and immune status) may choose to receive a second booster.

COVID-19 Vaccine Information

At the time of this publication, three COVID-19 vaccines are currently approved under a BLA or authorized under an EUA by FDA:

  • Pfizer-BioNTech COVID-19 Vaccine/COMIRNATY
  • Moderna COVID-19 Vaccine/SPIKEVAX
  • Janssen (Johnson & Johnson) COVID-19 Vaccine

For primary and booster vaccination for all populations, an mRNA COVID-19 vaccine series is preferred over the Janssen COVID-19 Vaccine.

COVID-19 vaccines are rapidly emerging and additional EUAs and BLA’s are likely to materialize. ACOG will strive to update this guidance as quickly as possible while maintaining accurate, evidence-based information.

mRNA COVID-19 Vaccines (Pfizer-BioNtech and Moderna)

The development and use of mRNA vaccines is relatively new. These vaccines consist of messenger RNA (mRNA) encapsulated by a lipid nanoparticle (LNP) for delivery into the host cells. These vaccines utilize the body’s own cells to generate the coronavirus spike protein (the relevant antigens), which, similar to all other vaccines, stimulates immune cells to create antibodies against COVID-19. The mRNA vaccines are not live virus vaccines, nor do they use an adjuvant to enhance vaccine efficacy. These vaccines do not enter the nucleus and do not alter human DNA in vaccine recipients. As a result, mRNA vaccines cannot cause any genetic changes (CDCZhang 2019Schlake 2012). Based on the mechanism of action of these vaccines and the demonstrated safety and efficacy in Phase II and Phase III clinical trials, it is expected that the safety and efficacy profile of the vaccine for pregnant individuals would be similar to that observed in nonpregnant individuals. Further, a growing body of observational data so far have not identified any safety concerns for COVID-19 vaccination during pregnancy.

Adenovirus-Vector Vaccines (J&J/Janssen Biotech Inc.)

The Janssen (J&J/Janssen) COVID-19 vaccine (Ad26.COV2.S) is based on the AdVac® technology platform and is a monovalent vaccine composed of a recombinant, replication-incompetent human adenovirus type 26 (Ad26) vector, constructed to encode a stabilized form of the SARS-CoV-2 Spike (S) protein. The Ad26 vector cannot replicate following administration to humans, and available data demonstrate that it is cleared from tissues following injection (FDA 2021).

Ad26.COV2.S is not a live virus vaccine, it does not contain preservatives, and it does not replicate in the cells. Based on data from ongoing and completed clinical trials of Ad26-vectored vaccines including COVID-19, HIV, and Ebola administered to pregnant individuals, overall, the Ad26-based vaccines have an acceptable safety and reactogenicity profile. In addition, the review of the available pregnancy data is not suggestive of a pregnancy-related safety concern (FDA 2021).

Efficacy of Available COVID-19 Vaccines

All currently available COVID-19 vaccines have demonstrated high efficacy among their respective clinical trial endpoints. Additionally, a growing body of evidence suggests that fully vaccinated people are less likely to have asymptomatic infection or transmit SARS-CoV-2 to others. Finally, emerging data indicate that while individuals may still become infected with COVID-19, those who are up to date on their COVID-19 vaccines, including boosters, are less likely to experience severe illness and serious adverse outcomes as a result of SARS-CoV-2 infection (Barda 2021).

mRNA vaccines

Based on results from clinical trials, the Pfizer-BioNTech COVID-19 vaccine was 95% effective at preventing laboratory-confirmed COVID-19 illness in people who received two doses who had no evidence of previous infection (CDC).

Based on results from clinical trials, the Moderna vaccine was 94.1% effective at preventing laboratory-confirmed COVID-19 illness in people who received two doses who had no evidence of being previously infected (CDC).

A prospective cohort study from two academic centers found that vaccinated pregnant and lactating women produced comparable immune responses to nonpregnant controls, and generated higher antibody titers than those observed following SARS-CoV-2 infection in pregnancy. Further, vaccine-generated antibodies were present in umbilical cord blood and breast milk after maternal vaccination (Gray 2021Prabhu 2021Juncker 2021).

Each of these vaccines appeared to have high efficacy in clinical trials among people of diverse age, sex, race, and ethnicity categories and among persons with underlying medical conditions. Further, during the rollout of COVID-19 vaccines, data continue to demonstrate high vaccine efficacy in preventing hospitalization and death (ACIP Slides).

Adenovirus-Vector vaccines

Based on the results from clinical trials in the U.S., the J&J/Janssen COVID-19 vaccine has been shown to be 66.9% effective at preventing moderate/severe COVID-19 illness and 76.7% effective at preventing severe/critical COVID-19 illness after a single dose. This vaccine also demonstrated 93.1% effectiveness at preventing hospitalizations 14 days following vaccination (Janssen 2021).

Safety of Available COVID-19 Vaccines

Side Effects

Expected side effects should be explained during counseling, including that they are a normal part of the body’s reaction to the vaccine and developing antibodies to protect against COVID-19 illness.

Most study participants for both the Pfizer-BioNTech and Moderna vaccines experienced mild side effects similar to influenza-like illness symptoms following vaccination (see Table 1 below). In the Pfizer-BioNTech study subgroup of persons aged 18–55 years, fever greater than 38 °C occurred in 3.7% after the first dose and 15.8% after the second dose (FDA 2020). In the Moderna vaccine trials, fever greater than 38°C was reported in 0.8% of vaccine recipients after the first dose, and 15.6% of vaccine recipients after the second dose (FDA 2020). Most of these symptoms resolved by day 3 after vaccination for both vaccines.

As is typical with adenovirus vaccines, side effects for the J&J/Janssen COVID-19 vaccine were generally mild and transient, resolving in 1–2 days following vaccination among safety study participants. In the J&J/Janssen safety study group, 9.0% of individuals receiving a COVID-19 vaccine experienced fever greater than 38°C following vaccination. Fever had a median duration of 1 day (FDA 2021).

Patients should be counseled about more severe side effects and when to seek medical care. For more information and details on side effects, see Local Reactions, Systemic Reactions, Adverse Events, and Serious Adverse Events: Pfizer-BioNTech COVID-19 Vaccine from the CDC.

Table 1. Mild Side Effects Among All Study Participants*

Injection Site ReactionsFatigueChillsMuscle PainJoint Pain Headaches
Moderna91.6%68.5%43.4% 59.6% 44.8% 63%
Pfizer-BioNTech84.10%62.90%31.90%38.30%23.60% 55.10%
J&J/Janssen48.6% 38.2% N/A 33.2% N/A 38.9%

*Fever was the least common side effect reported; see text above for data on frequency of fever

Allergic Reactions Including Anaphylaxis

Allergic reactions including anaphylaxis have been reported to be rare following COVID-19 vaccination in nonpregnant individuals. Anaphylaxis has been observed in 5 cases per million doses administered for the Pfizer-BioNTech vaccine, 4.9 cases per million doses administered of the Moderna vaccine, and 7.6 cases per million doses administered for the J&J/Janssen vaccine (ACIP August 2021).

If anaphylaxis is suspected in a pregnant individual after receiving a COVID-19 vaccination, anaphylaxis should be managed the same as in nonpregnant individuals (e.g., rapidly assess airway, breathing, circulation, and mental activity; call for emergency medical services; place the patient in a supine position, and administration of epinephrine) (CDC). Similar to nonpregnant individuals, anaphylaxis may recur after the individual begins to recover, and monitoring in a medical facility for at least several hours is advised, even after complete resolution of symptoms and signs.

For more information on the management of anaphylaxis after COVID-19 vaccination, see CDC’s website.

Thrombosis with Thrombocytopenia Syndrome

Background

FDA has added a warning about the possibility of thrombosis with thrombocytopenia syndrome (TTS) to the J&J/Janssen COVID-19 vaccine EUA and fact sheets regarding this syndrome. The EUA fact sheet should be provided to all vaccine recipients and their caregivers before vaccination with any authorized COVID-19 vaccine.

Considerations for Women of Reproductive Age and Pregnant Individuals

Most cases of TTS reported to the Vaccine Adverse Event Reporting System (VAERS) following receipt of the J&J/Janssen COVID-19 vaccine to date have occurred in women of reproductive age. None of these individuals were pregnant. While TTS is a clinically serious condition, it is critical to emphasize the rarity of this syndrome, which has occurred in approximately 10.6 out of every million doses of J&J/Janssen COVID-19 vaccine administered to females aged 30–39 years and 9.02 per million doses of J&J/Janssen COVID-19 vaccine administered to females aged 40–49 years (See 2021).

Currently available data suggest a causal relationship between J&J/Janssen COVID-19 vaccine with TTS. Although the condition is rare, based on an updated risk/benefit analysis, use of mRNA vaccines is preferred for all vaccine-eligible persons, including pregnant and lactating people. The J&J/Janssen vaccine remains an option for vaccination when there is a contraindication to mRNA COVID-19 vaccines, when a person would otherwise remain unvaccinated due to limited access to mRNA vaccines, or when a person expresses an informed preference for the J&J/Janssen COVID-19 vaccine. Any person who receives a J&J/Janssen COVID-19 vaccine should be aware of the rare risk of TTS after receipt of this vaccine and that mRNA COVID-19 vaccines are preferred.  Of note, a history of TTS following receipt of the J&J/Janssen COVID-19 vaccine or any other adenovirus vector–based COVID-19 vaccines (e.g. such as AstraZeneca’s COVID-19 vaccine, which is not authorized or approved for use in the United States) is considered a contraindication to administration of additional doses of the J&J/Janssen COVID-19 vaccine.

Although the overall general risk of thrombosis is increased during pregnancy and the postpartum period, and with certain hormonal contraceptives, experts believe that these factors do not make people more susceptible to TTS after receipt of the J&J/Janssen COVID-19 vaccine. Given these differing mechanisms, there is no recommendation to discontinue or change hormonal contraceptive methods in women who have received or plan to receive the J&J/Janssen COVID-19 vaccine. Additionally, people who take aspirin or anticoagulants as part of their routine medications, including during pregnancy, do not need to stop or alter the dose of these medications prior to receipt of the J&J/Janssen COVID-19 vaccine (CDC Clinical Considerations).

Diagnosis and Treatment

Patients receiving the J&J/Janssen COVID-19 vaccine should be informed of symptoms of TTS, including severe headache, visual changes, abdominal pain, nausea and vomiting, back pain, shortness of breath, leg pain or swelling, petechiae, easy bruising, or bleeding. Patients who experience these symptoms should be counseled to seek immediate medical evaluation. Symptoms most commonly appear 6–14 days following vaccination (ASH).

The American Society for Hematology (ASH) has issued guidance related to diagnosing and managing TTS. Of critical importance, TTS should not be treated with the same drugs used to treat other blood clots. Specifically, heparin should not be used to treat TTS. See the ASH guidance for more details on diagnosis and treatment protocols for TTS.

Myocarditis and Pericarditis

Since April 2021, cases of myocarditis (ranging from 1 per 100,000 to 2.13 per 100,000) and pericarditis (1.8 per 100,000) have been reported in the United States after mRNA COVID-19 vaccination (Pfizer-BioNTech and Moderna), particularly in adolescents and young adults (Diaz 2021Witberg 2021). There has not been a similar reporting pattern observed after receipt of the J&J/Janssen COVID-19 vaccine. Reported cases have occurred predominantly in male adolescents and young adults aged 16 years and older. Onset was typically within several days after mRNA COVID-19 vaccination, and cases have occurred more often after the second dose than the first dose. Surveillance of these cases following mRNA COVID-19 vaccination are ongoing.

Clinicians should consider the diagnoses of myocarditis and pericarditis in adolescents or young adults with acute chest pain, shortness of breath, or palpitations. In this population, coronary events are less likely to be a source of these symptoms. In most cases, patients who presented for medical care have responded well to medications and rest and had prompt improvement of symptoms. Clinicians should report all cases of myocarditis and pericarditis post COVID-19 vaccination to VAERS.

For more information, see CDC and the American Heart Association.

Guillain-Barré Syndrome

Multiple safety systems have reported a higher-than expected number of cases of Guillain-Barré syndrome following the use of the J&J/Janssen COVID-19 vaccine. However, investigations into this complex diagnosis are ongoing and additional information is needed to fully understand the potential relationship between Guillain-Barré syndrome and the J&J/Janssen COVID-19 vaccine. It appears the absolute risk of Guillain-Barré syndrome following vaccination remains very low (estimated crude reporting rate of 1 per 100,000 doses); therefore, the benefits of prevention of severe COVID-19 illness through vaccination outweigh this very rare risk (Woo 2021).

Available Safety Information Related to the Use of COVID-19 Vaccines in Pregnancy

Despite ACOG’s persistent advocacy for the inclusion of pregnant individuals in COVID-19 vaccine trials, none of the COVID-19 vaccines approved under EUA have been tested in pregnant individuals. However, studies in pregnant women have begun and post-market surveillance is underway.

Developmental and Reproductive Toxicity Data

Data from Developmental and Reproductive Toxicity (DART) studies for the Pfizer-BioNTech COVID-19 vaccine have been reported in Europe. According to the report presented to the European Medicines Agency, animal studies using the Pfizer/BioNTech COVID-19 vaccine do not indicate direct or indirect harmful effects with respect to pregnancy, embryo/fetal development, parturition, or postnatal development (EMA).

A combined developmental and perinatal/postnatal reproductive toxicity (DART) study of Moderna’s mRNA-1273 in rats was submitted to FDA on December 4, 2020. FDA review of this study concluded that mRNA1273 given prior to mating and during gestation periods at dose of 100 µg did not have any adverse effects on female reproduction, fetal/embryonal development, or postnatal developmental except for skeletal variations, which are common and typically resolve postnatally without intervention (FDA).

In a reproductive developmental toxicity study, female rabbits were administered 1 mL of the J&J/Janssen COVID-19 vaccine (a single human dose is 0.5 mL) by intramuscular injection 7 days prior to mating and on gestation days 6 and 20 (i.e., one vaccination during early and late gestation, respectively). No vaccine-related adverse effects on female fertility, embryo-fetal or postnatal development up to postnatal day 28 were observed (FDA 2021). Further, based on data from ongoing and completed clinical trials of Ad26-vectored vaccines including COVID-19, HIV, and Ebola administered to pregnant individuals, overall, the Ad26-based vaccines have an acceptable safety and reactogenicity profile, without significant safety issues identified to date. In addition, the review of the available pregnancy data is not suggestive of a pregnancy-related safety concern (FDA 2021).

These DART studies provided the first safety data to help inform the use of the vaccine in pregnancy.

Among participants of Phase II/III COVID-19 vaccine clinical studies in nonpregnant adults, a few inadvertent pregnancies that have occurred are being followed to collect safety outcomes.

Post-Administration Pregnancy Surveillance Data

As of February 14, 2022, there have been over 201,000 pregnancies reported in CDC’s v-safe post-vaccination health checker (CDC 2021). Based on limited self-reported information, no specific safety signals have been observed in pregnant people enrolled in v-safe; however longitudinal follow-up is needed.

CDC is currently enrolling pregnant individuals in a v-safe pregnancy registry, and as of April 25, 2022, 23,711 pregnant individuals were enrolled. Data collected through February 28 from the v-safe pregnancy registry did not indicate any safety concerns based on the reactogenicity profile and adverse events observed among pregnant individuals. Additionally, side effects were similar in pregnant and nonpregnant populations. Specific neonatal outcomes data published in The New England Journal of Medicine, along with pregnancy complication data from 275 completed pregnancies presented at the March 1, 2021 ACIP meeting are included in Table 2.

No differences have been seen when comparing pregnant individuals participating in the v-safe pregnancy registry with the background rates of adverse pregnancy outcomes. It appears that the spontaneous abortion rate following COVID-19 vaccination during pregnancy is consistent with the background rate; however the ideal denominator has not appeared in published literature (Shimabukuro 2021). Data reported by CDC indicate that the proportion of spontaneous abortions reported after COVID-19 vaccination is consistent with the known background rate of this outcome. However, a risk estimate has not yet been established (Shimabukuro 2021Zauche 2021).

In addition to data reported from the v-safe pregnancy registry, multiple reports from the Vaccine Safety Datalink (VSD) continue to reinforce the safety of COVID-19 vaccination during pregnancy. A case-control study using data from the VSD found that among women with spontaneous abortions, the odds of COVID-19 vaccine exposure were not increased in the prior 28 days compared with women with ongoing pregnancies (Kharbanda 2021). In a subsequent retrospective cohort of >40,000 pregnant women in the VSD, COVID-19 vaccination during pregnancy was not associated with preterm birth or small-for-gestational age at birth overall, stratified by trimester of vaccination, or number of vaccine doses received during pregnancy, compared with unvaccinated pregnant women (Lipkind 2022).

In a research letter published in April 2022, investigators evaluated the association between COVID-19 vaccination during early pregnancy and risk of major fetal structural anomalies identified on ultrasonography. Of 2622 patients who received at least 1 dose of COVID-19 vaccine, 1149 (43.8%) were vaccinated within the teratogenic window. Results of this analysis found that vaccination within the teratogenic window was not associated with presence of a congenital anomaly identified on ultrasonography (Ruderman 2022).

Table 2. V-safe Pregnancy Registry Outcomes of Interest in COVID-19-Vaccinated Pregnant Individuals

Pregnancy ComplicationsBackground RateV-safe Pregnancy Registry Overall
Neonatal Outcomes*Background RateV-safe Pregnancy Registry Overall
Gestational diabetes7-14%10%
Preeclampsia or gestational hypertension10-15%15%
Eclampsia0.27%0%
Intrauterine growth restriction3-7%1%
Preterm birth8-15%9.4%
Congenital anomalies3%2.2%
Small for gestational age3.5%3.2%
Neonatal death0.38%0%

*Shimabukuro TT, Kim SY, Myers TR, Moro PL, Oduyebo T, Panagiotakopoulos L, et al. Preliminary findings of mRNA Covid-19 vaccine safety in pregnant persons. CDC v-safe COVID-19 Pregnancy Registry Team [published online April 21, 2021]. N Engl J Med. DOI: 10.1056/NEJMoa2104983. Available at: https://www.nejm.org/doi/10.1056/NEJMoa2104983.

Shimabukuro T. COVID-19 vaccine safety update. Advisory Committee on Immunization Practices (ACIP). Atlanta, GA: Centers for Disease Control and Prevention; 2021. Available at: https://www.cdc.gov/vaccines/acip/meetings/downloads/slides-2021-02/28-03-01/05-covid-Shimabukuro.pdf. Retrieved March 1, 2021.

Evidence will continue to be gathered through these systems and will provide clinicians with critically needed data to inform future recommendations related to COVID-19 vaccination during pregnancy (ACIP slides).

General Recommendations and Considerations

ACOG strongly recommends that all eligible persons aged 12 years and older, including pregnant and lactating individuals, receive a COVID-19 vaccine or vaccine series. Obstetrician–gynecologists and other women’s health care practitioners should lead by example by being vaccinated and encouraging eligible patients to be vaccinated as well. See Table 3 for COVID-19 vaccine recommendations by product.

  • mRNA COVID-19 vaccines are preferred over J&J/Janssen COVID-19 vaccine for most individuals, including pregnant and lactating individuals, for primary series, primary additional doses (for immunocompromised persons), and booster vaccination.
    • The J&J/Janssen COVID-19 vaccine remains an option for vaccination when there is a contraindication to mRNA COVID-19 vaccines, when a person would otherwise remain unvaccinated due to limited access to mRNA vaccines, or when a person expresses an informed preference for the J&J/Janssen COVID-19 vaccine.
    • Individuals age 12 to 17 years are only eligible to receive the Pfizer-BioNTech vaccine at this time.
  • Individuals who receive either the Pfizer-BioNTech or Moderna COVID-19 vaccine should complete their primary two-dose series with the same vaccine product
  • COVID-19 vaccines may be administered simultaneously with other vaccines, including within 14 days of receipt of another vaccine. This includes vaccines routinely administered during pregnancy, such as influenza and Tdap.
  • Precautions should be discussed with any individual who reports a history of any immediate allergic reaction to any other vaccine or injectable therapy (i.e., intramuscular, intravenous, or subcutaneous vaccines or therapies not related to a component of COVID-19 vaccines or polysorbate) (CDC). Locations administering COVID-19 vaccines should adhere to CDC guidance for use of COVID-19 vaccines, including screening recipients for contraindications and precautions, having the necessary supplies available to manage anaphylaxis, implementing the recommended postvaccination observation periods, and immediately treating suspected cases of anaphylaxis with intramuscular injection of epinephrine (CDC).
  • Individuals, including those who are pregnant and/or lactating, with a history of SARS-CoV-2 infection should receive a COVID-19 vaccine. 
  • Individuals who receive a COVID-19 vaccine should be educated about and encouraged to participate in CDC’s v-safe program (see below for more information on CDC’s v-safe program).
  • Obstetrician–gynecologists are encouraged to assess and document patients’ COVID-19 vaccination status in the medical record.
  • Moderately to severely immunocompromised individuals (i.e., people who have undergone solid organ transplantation or have been diagnosed with conditions that are considered to have an equivalent level of immunocompromise) should receive an additional dose (i.e., an additional primary dose) of an mRNA COVID-19 vaccine after an initial two-dose primary mRNA COVID-19 vaccine series. The additional dose should be administered at least 28 days after the completion of the initial mRNA COVID-19 vaccine series.
  • All individuals aged 12 years and older who received an initial COVID-19 vaccine or vaccine series should receive a single booster dose of COVID-19 vaccine.
    • Individuals who received J&J/Janssen vaccine should receive a COVID-19 booster at least 2 months following their initial vaccine.
    • Individuals who received an mRNA vaccine should receive a booster 5 months following their initial vaccine series.
  • Individuals may receive any vaccine product available to them for their booster dose; they do not have to receive the same product as their initial vaccine or vaccine series; however:
    • The mRNA vaccines are preferred over the J&J/Janssen COVID-19 vaccine.
    • Adolescents aged 12–17 years are eligible for only the Pfizer-BioNTech COVID-19 vaccine.

Immunocompromised Individuals

Moderately to severely immunocompromised individuals (i.e., people who have undergone solid organ transplantation or have been diagnosed with conditions that are considered to have an equivalent level of immunocompromise) should receive an additional dose (i.e., an additional primary dose) of COVID-19 vaccine after their initial vaccine or vaccine series. The additional dose should be administered four weeks after the completion of the initial COVID-19 vaccine or vaccine series. For mRNA vaccines, this means immunocompromised individuals need a 3-dose primary series. For J&J/Janssen vaccine, immunocompromised individuals need a 2-dose primary series with the second dose being an mRNA vaccine.

Booster Doses

All individuals aged 12 years and older who received an initial COVID-19 vaccine or vaccine series should receive a single booster dose of COVID-19 vaccine.

  • Individuals who received J&J/Janssen vaccine should receive a COVID-19 booster at least 2 months following their initial vaccine
  • Individuals who received an mRNA vaccine should receive a booster at least 5 months following their initial vaccine series

Individuals may receive any vaccine product available to them for their booster dose; they do not have to receive the same product as their initial vaccine or vaccine series; however:

  • The mRNA vaccines are preferred over the J&J/Janssen COVID-19 vaccine
  • Adolescents aged 12–17 years are eligible for only the Pfizer-BioNTech COVID-19 vaccine

Moderately to severely immunocompromised individuals should receive a booster dose following their primary 2- or 3-dose series:

mRNA COVID-19 Vaccines

Moderately to severely immunocompromised individuals should receive a booster dose at least 3 months following their third primary series (additional) dose, preferably with an mRNA vaccine. If Moderna vaccine is used for the booster dose, a 50 mcg (0.25 mL) dose should be used.

J&J/Janssen COVID-19 Vaccine

A single booster dose is recommended at least 2 months after the 2nd (additional) dose, for a total of 3 doses (1 Janssen vaccine dose followed by 1 additional mRNA vaccine dose, then 1 booster dose). mRNA vaccines are preferred for the booster dose. If the Moderna vaccine is used for the booster dose, a 50 mcg (0.25 ml) dose should be used.

Some individuals may choose to receive a second booster at least 4 months after their first booster depending on age, vaccine product received for their initial series and booster, or if they are immunocompromised. See Table 3 and CDC for details.

Table 3. COVID-19 Vaccine Recommendations by Product

Vaccine ProductAge IndicationNumber of Doses in Primary SeriesAdditional Dose for Moderately-Severely Immunocompromised individualsBooster DoseSecond Booster Dose
Pfizer-BioNTech5+ years2 dosesAdministered 3–8 weeks* apart1 additional dose for individuals 5+ yearsAdministered 28 days after the 2nd dose (3 dose primary series)Single booster dose at least 5 months after the last primary series dose for individuals 12+Individuals age 12 and older can only get Pfizer-BioNTechA second booster dose at least 4 months after the first booster may be given to moderately or severely immunocompromised individuals and individuals age 50 years and older
Moderna18+ years2 dosesAdministered 4–8 weeks* apart1 additional dose for individuals 18+ yearsAdministered 28 days after the 2nd dose (3 dose primary series)Single booster dose at least 5 months after the last primary series dose for individuals 18+Moderna or Pfizer-BioNTech preferredA second booster dose at least 4 months after the first booster may be given to moderately or severely immunocompromised individuals, individuals age 50 years and older
J&J/Janssen18+ years1 dose1 additional dose of a mRNA COVID vaccine for individuals 18+ yearsAdministered 28 days after the 1st dose (2 dose primary series)The second dose should be a mRNA COVID-19 vaccineSingle booster dose at least 2 months after the first J&J/Janssen dose for individuals 18+Individuals age 18 and older should get either a Pfizer-BioNTech or Moderna boosterA second booster dose at least 4 months after the first booster may be given to moderately or severely immunocompromised individuals, individuals age 50 years and older, and people aged 18–49 years who are not moderately or severely immunocompromised and who received Janssen COVID-19 Vaccine as both their primary series dose and booster dose (must be an mRNA vaccine)

*An 8-week interval may be optimal for some people ages 12 years and older, especially for males ages 12 to 39 years. A shorter interval (3 weeks for Pfizer-BioNTech; 4 weeks for Moderna) between the first and second doses remains the recommended interval for: people who are moderately or severely immunocompromised; adults ages 65 years and older; and others who need rapid protection due to increased concern about community transmission or risk of severe disease.

The J&J/Janssen vaccine remains an option for vaccination when there is a contraindication to mRNA COVID-19 vaccines, when a person would otherwise remain unvaccinated due to limited access to mRNA vaccines, or when a person expresses an informed preference for the J&J/Janssen COVID-19 vaccine.

Obstetric Care Recommendations and Considerations

Pregnant Individuals

COVID-19 Infection Risk in Pregnancy

Pregnant and recently pregnant patients with COVID-19 are at increased risk of more severe illness compared with nonpregnant peers (Ellington MMWR 2020Collin 2020Delahoy MMWR 2020Khan 2021). Available data indicate an increased risk of ICU admission, need for mechanical ventilation and ventilatory support (ECMO), and death reported in pregnant women with symptomatic COVID-19 infection, when compared with symptomatic nonpregnant women (Zambrano MMWR 2020Khan 2021). Pregnant and recently pregnant patients with comorbidities such as obesity and diabetes may be at an even higher risk of severe illness consistent with the general population with similar comorbidities (Ellington MMWR 2020Panagiotakopoulos MMWR 2020Knight 2020Zambrano MMWR 2020Allotey 2020Metz 2021Galang 2021).

COVID-19 Vaccination

ACOG strongly recommends that pregnant individuals be vaccinated against COVID-19. The mRNA COVID-19 vaccines are preferred over the J&J/Janssen COVID-19 vaccine for pregnant individuals, similar to nonpregnant individuals. As of April 16, 2022, about 69% of pregnant individuals have been fully vaccinated against COVID-19 (CDC COVID Data Tracker). Given the potential for severe illness and death during pregnancy, the importance of completion of the initial COVID-19 vaccination series should be emphasized for this population. A recent study in Scotland found that most cases of SARS-CoV-2 infection during pregnancy were among unvaccinated individuals (Stock 2022). Further, data from the U.S. have indicated that among pregnant people with COVID-19, those who were vaccinated experienced less severe illness (Morgan 2022). Obstetrician–gynecologists and other obstetric care providers should routinely assess their pregnant patients’ vaccination status. On the basis of this assessment, they should recommend needed vaccines to their pregnant patients.

There is no evidence of adverse maternal or fetal effects from vaccinating pregnant individuals with COVID-19 vaccine, and a growing body of data demonstrate the safety of such use (Ciapponi 2021Wainstock 2021Kachikis 2021Magnus 2021Fu 2021Ruderman 2022). Therefore, individuals who are or will be pregnant should receive the COVID-19 vaccine. Emerging data indicate that vaccine-induced antibodies cross the placenta, but the degree of protection these antibodies provide to the neonate is unknown (Yang 2022). In a recent case-control study from 20 pediatric hospitals, CDC found that COVID-19 vaccination during pregnancy reduced the risk of infant hospitalization with COVID-19 by 61%, suggesting that COVID-19 vaccination during pregnancy might also help protect babies. These findings emphasize the importance of COVID-19 vaccination during pregnancy to protect pregnant people and their babies from COVID-19 (Halasa 2022). Vaccination may occur in any trimester and emphasis should be on vaccine receipt as soon as possible to maximize maternal and fetal health.

COVID-19 Booster During Pregnancy

Due to the potential for severe illness and death from SARS-CoV-2 infection during pregnancy, in addition to waning immunity (ACIP slides), ACOG recommends that pregnant and recently pregnant people up to 6 weeks postpartum receive a booster dose of COVID-19 vaccine following the completion of their initial COVID-19 vaccine or vaccine series. Specifically:

INITIAL BOOSTER
  • Pregnant and recently pregnant people who received J&J/Janssen vaccine should receive a COVID-19 booster at least 2 months following their initial vaccine.
  • Pregnant and recently pregnant people who received an mRNA vaccine should receive a booster at least 5 months following their initial vaccine series.
  • Pregnant and recently pregnant people can receive any COVID-19 vaccine available to them for their booster dose; it does not have to be the same product as their initial vaccine or vaccine series; however:
    • The mRNA vaccines are preferred over the J&J/Janssen COVID-19 vaccine.
    • Adolescents aged 12–17 years are eligible for only the Pfizer-BioNTech COVID-19 vaccine.

These recommendations also apply to pregnant and recently pregnant (e.g., up to 6 weeks postpartum) individuals who completed their initial COVID-19 vaccine or vaccine series prior to pregnancy.

SECOND BOOSTER

Pregnancy alone is not an indication for a second booster. However, pregnant patients who meet other criteria (age, vaccine product received for primary series and booster, and immune status) may choose to receive a second booster.

As stated above, efforts should be focused on increasing the initial series of COVID-19 vaccination among pregnant people.

COVID-19 Vaccine Counseling

Individuals should have access to available information about the safety and efficacy of the vaccine. A conversation between the patient and their clinical team may assist with decisions regarding COVID-19 vaccination during pregnancy. Important considerations include the potential efficacy of the vaccine, the potential risk and severity of maternal disease, including the effects of disease on the fetus and newborn, and the safety of the vaccine for the pregnant patient and the fetus. While pregnant individuals are encouraged to discuss vaccination considerations with their clinical care team when feasible, written permission or documentation of such a discussion should not be required prior to receiving a COVID-19 vaccine.

When recommending the COVID-19 vaccine, clinicians should review the available data on risks and benefits of vaccination with pregnant patients, including the risks of not getting vaccinated in the context of the individual patient’s current health status and risk of exposure, including the possibility for exposure at work or home and the possibility for exposing high-risk household members. Conversations about risk should take into account the individual patient’s values and perceived risk of various outcomes and should respect and support autonomous decision-making (ACOG 2013).

Any of the currently authorized COVID-19 vaccines can be administered to pregnant, recently pregnant, or lactating people; however, the mRNA COVID-19 vaccines are preferred over the J&J/Janssen COVID-19 vaccine for all persons, including pregnant, recently pregnant, and lactating people.

Additional Vaccination Considerations for Pregnant Individuals

  • Similar to their nonpregnant peers, vaccination of pregnant individuals with a COVID-19 vaccine may occur in any setting authorized to administer these vaccines. This includes any clinical setting and nonclinical community-based vaccination sites such as schools, community centers, and other mass vaccination locations.
  • Pregnant individuals who experience fever following vaccination should be counseled to take acetaminophen. Acetaminophen has been proven to be safe for use in pregnancy and does not appear to impact antibody response to COVID-19 vaccines.
  • Anti-D immunoglobulin (i.e. Rhogam) should not be withheld from an individual who is planning or has recently received a COVID-19 vaccine as it will not interfere with the immune response to the vaccine.
  • For patients who do not receive any COVID-19 vaccine, the discussion should be documented in the patient’s medical record. During subsequent office visits, obstetrician–gynecologists should address ongoing questions and concerns and offer vaccination again. Clinicians should reinforce the importance of other prevention measures such as hand washing, physical distancing, and wearing a mask.

Lactating Individuals

ACOG strongly recommends that lactating individuals be vaccinated against COVID-19. While lactating individuals were not included in most clinical trials, COVID-19 vaccines should not be withheld from lactating individuals who otherwise meet criteria for vaccination. Theoretical concerns regarding the safety of vaccinating lactating individuals do not outweigh the potential benefits of receiving the vaccine, and a growing body of evidence demonstrates that COVID-19 vaccination is safe during lactation (Bertrand 2021Kachikis 2021). Further, current data demonstrate that lactating people who have received mRNA COVID-19 vaccines have antibodies in their breast milk, suggesting a potential protective effect against infection in the infant, although the degree of clinical benefit is not yet known (Perl 2021Young 2021). There is no need to avoid initiation or discontinue breastfeeding in patients who receive a COVID-19 vaccine (ABM 2020).

Information for pregnant and lactating patients can be found on ACOG’s patient website: Coronavirus (COVID-19), Pregnancy, and Breastfeeding: A Message for Patients.

Gynecologic Care Recommendations and Considerations

Individuals Contemplating Pregnancy

Vaccination is strongly recommended for nonpregnant individuals aged 12 years and older. Further, ACOG recommends vaccination for individuals who are actively trying to become pregnant or are contemplating pregnancy. Additionally, it is not necessary to delay pregnancy after completing both doses of the COVID-19 vaccine.

Claims linking COVID-19 vaccines to infertility are unfounded and have no scientific evidence supporting them. Given the mechanism of action and the safety profile of the mRNA vaccines in nonpregnant individuals, COVID-19 mRNA vaccines are not a cause of infertility. Adenovirus vector vaccines such as the J&J/Janssen COVID-19 vaccine cannot replicate following administration, and available data demonstrate that it is cleared from tissues following injection. Because it does not replicate in the cells, the vaccine cannot cause infection or alter the DNA of a vaccine recipient and is also not a cause of infertility (Evans, 2021Morris 2021). Additionally, a growing body of data demonstrate that COVID-19 vaccines do not negatively impact fertility. In a prospective cohort study of couples trying to conceive, no meaningful association between COVID-19 vaccination in either partner with fecundability was found (Wesselink 2022). Further, a study from the Icahn School of Medicine at Mount Sinai investigated fertility outcomes after COVID-19 vaccination, including egg quality, embryo quality and development, pregnancy rates, and early miscarriage. The study showed no differences in rates of adverse outcomes in vaccinated compared to unvaccinated patients (Aharon 2022). Therefore, ACOG recommends vaccination for all eligible people who may consider future pregnancy.

If an individual becomes pregnant after the first dose of a COVID-19 vaccine requiring two doses (Pfizer-BioNTech or Moderna), the second dose and booster dose should be administered as indicated.

Finally, routine pregnancy testing is not recommended and should not be required prior to receiving any EUA-approved COVID-19 vaccine.

Routine Mammography

Reports of some patients developing temporary contralateral or ipsilateral lymphadenopathy after a COVID-19 vaccination have raised concerns about the possible effect on interpretation of mammogram screening results. A Radiology Expert Scientific Panel has issued a recommendation that mammograms should be conducted prior to COVID-19 vaccination or postponed, if possible, for 4–6 weeks following the second vaccine dose to avoid uncertainty in interpretation of mammogram results.

Screening mammograms are an essential part of preventive care, so postponing screening should only be considered when it does not unduly delay care. If a mammogram is performed fewer than 4–6 weeks after COVID-19 vaccination, patients should inform the mammogram technologist or radiologist when the vaccine was administered, which vaccine was received, and in which arm to aid in interpretation of screening results.

Reports of Post-Vaccination Menstrual Changes

There have been anecdotal reports of temporary changes in menstruation patterns (e.g., heavier menses, early or late onset, and dysmenorrhea) in individuals who have recently been vaccinated for COVID-19. While environmental stresses can temporarily impact menses, vaccines have not been previously associated with menstrual changes. A prospective study of nearly 4,000 women found a temporary non-clinically significant change in cycle length of less than 1 day, and no change in the length of menstrual bleeding. These temporary small variations in cycle length attenuated quickly within two postvaccine cycles (Edelman 2022). The data support that any effect of the COVID-19 vaccines on menstruation is minimal and temporary and should not be a reason for individuals to avoid vaccination. ACOG will continue to monitor and evaluate available evidence on this issue.

Additionally, there is no reason for individuals to schedule their vaccinations based on their menstrual cycles; vaccines can be given to those currently menstruating.

Information for patients can be found on ACOG’s patient website: Coronavirus (COVID-19) and Women’s Health Care: A Message for Patients.

Health Equity Considerations and Communities of Color

Communities of color have been disproportionately affected by the COVID-19 pandemic. Individuals in communities of color are more likely to have severe illness and even die from COVID-19, likely due to a range of social and structural factors including disparities in socioeconomic status, access to care, rates of chronic conditions, occupational exposures, systemic racism, and historic and continued inequities in the health care system. Access to and confidence in COVID-19 vaccines is of critical importance for all communities, but willingness to consider vaccination varies by patient context, in part due to historic and continued injustices and systemic racism that has eroded trust in some communities of color. With time, greater proportions of Black Americans have expressed desire for vaccination such that the majority surveyed affirm their intent for vaccination (Pew Research Center, 2021). Despite intent to obtain vaccination, inequities in vaccine distribution persist. Recent data suggest that, while disparities in access have narrowed over recent months, Black and Latinx populations generally remain vaccinated at lower rates than others, in part related to differential access (Kaiser Family Foundation 2021). With the spread of the more transmissible variants, which most profoundly affect unvaccinated people, equitable vaccine access remains essential.

When discussing COVID-19 vaccines with an individual who expresses concerns, it is critical to:

  • Be aware of historical and current injustices perpetuated on communities of color.
  • Actively listen to and validate expressed fears and concerns while also addressing misinformation about the vaccine.
  • Be knowledgeable of the existing avenues for vaccine access in traditionally underserved communities.
  • For patients who do not receive the vaccine, the discussion should be documented in the patient’s medical record. During subsequent office visits, obstetrician–gynecologists should address ongoing questions and concerns and offer vaccination again.

If the patient is amenable to further discussion:

  • Inform about the testing process, existing safety data, and continued monitoring of safety and efficacy data on COVID-19 vaccines; there have not been shortcuts with the testing of this vaccine.
  • Discuss the increased incidence of infection and severe illness from COVID-19 in communities of color.
  • Connect patients to trust-building resources developed by people who may have shared experiences and identities (see below for resource examples).
  • Note that individuals from communities of color were included in clinical trials (9.8% of Pfizer-BioNTech overall Phase II/III participants were Black and 26.2% were Hispanic/Latinx; 9.7% of Moderna overall Phase II/III participants were Black and 20% were Hispanic/Latinx; 13% of J&J/Janssen overall Phase II/III participants were Black and 14.7% were Hispanic/Latinx), and the vaccine was equally effective among different demographics, including race and ethnicity.

Health Equity Considerations: J&J/Janssen COVID-19 Vaccine

As discussed earlier in the document, the safety of the J&J/Janssen COVID-19 vaccine has been closely investigated. While mRNA COVID-19 vaccines are preferred, the J&J/Janssen COVID-19 vaccine remains a safe and effective preventative measure against COVID-19 that offers flexibility in distribution and implementation that could improve vaccine uptake in specific circumstances. For example, the required refrigerator temperature storage is widely available allowing for vaccine availability in areas and distribution sites that would otherwise be unable to meet the storage requirements of other vaccine options. In addition, the one-dose vaccine may be preferred by some individuals who may face barriers to obtaining a second dose.

Balancing the official preference for mRNA vaccines over the J&J/Janssen COVID-19 Vaccine (based on risk of TTS in those who receive the J&J/Janssen COVID-19 vaccine and decreased efficacy when compared to mRNA vaccines) with the need for equitable distribution of all effective COVID-19 vaccines requires nuanced evaluations of individual risk profiles and social impacts to vaccine access and uptake. Risk–benefit conversations should include consideration of an individual’s likelihood of developing severe disease from COVID-19, barriers they may face to completing a one- or two-dose vaccine series, availability of different vaccine options, as well as an individual’s risk tolerance and vaccine acceptance. These discussions are critical to individualized care and ensuring that generalized recommendations do not negatively impact overall vaccine distribution inequities.

All eligible individuals should be counseled that the mRNA COVID-19 vaccines are preferred over J&J/Janssen COVID-19 vaccine. However, any vaccine is preferable to no vaccine, and individuals who express an informed preference for the J&J/Janssen COVID-19 vaccine should have the option of receiving one if available. If any individual makes an informed choice for one type of COVID-19 vaccine over another for any reason, this decision should be supported as vaccination with any product continues to be safer than remaining unvaccinated.

Additional Health Equity Resources

Vaccine Confidence

Vaccine hesitancy, particularly around COVID-19 vaccines, exists among all populations. When communicating with patients, it is extremely important to underscore the general safety of vaccines and emphasize the fact that no steps were skipped in the development and evaluation of COVID-19 vaccines. This can be done by briefly highlighting the safety requirements of vaccines, and ongoing safety monitoring even after vaccines are made available.

The following are some messages to consider using when discussing COVID-19 vaccines with patients:

  • Vaccines are one of the greatest public health achievements of the 20th century. Before the widespread use of vaccines, people routinely died from infectious diseases, several of which have since been eradicated thanks to robust immunization programs.
  • All available COVID-19 vaccines are highly effective. Individuals can be confident in the ability of each of the vaccines to provide a high level of protection from COVID-19 illness.
  • Community members may interpret the recent preference for mRNA vaccines over the J&J/Janssen COVID-19 vaccine to mean that the J&J/Janssen vaccine is not safe. However, as described above, these complications are rare events. While mRNA vaccines are preferred, J&J/Janssen COVID-19 vaccines are still available for individuals with a contraindication to mRNA COVID-19 vaccines, for persons who would otherwise remain unvaccinated due to limited access to mRNA vaccines, or when a person expresses an informed preference for the J&J/Janssen vaccine. Individuals should be aware of the rare risk of TTS after receipt of the J&J/Janssen COVID-19 vaccine and that other FDA-authorized COVID-19 vaccines (i.e., mRNA vaccines) are available and preferred.
  • Several vaccines have safely been given to pregnant and lactating individuals for decades.
  • To date, safety data on COVID-19 vaccines administered during pregnancy do not reveal any safety concerns.
  • The rigor of COVID-19 vaccine clinical trials with regards to monitoring safety and efficacy meet the same high standards and requirements as with a typical vaccine approval process.
  • While there has been a worldwide attempt to develop COVID-19 vaccines rapidly, this does not mean that any safety standards have been relaxed. In fact, there are additional safety monitoring systems to track and monitor these vaccines, including real-time assessment.
  • Side effects such as influenza-like illness can be expected with these vaccines; however, this is a normal reaction as the body develops antibodies to protect itself against COVID-19. COVID-19 vaccines cannot cause COVID-19 infection. It is important not to be dissuaded by these side effects, because in order to get the maximum protection against COVID-19, patients need two doses of the vaccine.
  • Safety monitoring continues well beyond the EUA administration.
    • COVID-19 Vaccine Monitoring Systems for Pregnant People
    • CDC V-Safe COVID-19 Vaccine Pregnancy Registry: A registry to collect additional health information from v-safe participants who report being pregnant at the time of vaccination or a positive pregnancy test after vaccination. This information helps CDC monitor the safety of COVID-19 vaccines in people who are pregnant. V-safe is a new smartphone-based, after-vaccination health checker for people who receive COVID-19 vaccines. V-safe uses text messaging and web surveys from CDC to check in with vaccine recipients following COVID-19 vaccination. V-safe also provides second vaccine dose reminders if needed, and telephone follow-up for anyone who reports a symptom or health condition for which they seek medical attention.
    • CDC’s V-Safe: A new active surveillance smartphone-based after-vaccination health checker for people who receive COVID-19 vaccines. V-safe will use text messaging and web surveys from CDC to check in with vaccine recipients for health problems following COVID-19 vaccination. Information on pregnancy status at the time of vaccination and at subsequent follow-up time points will also be collected. The system will provide telephone follow-up to anyone who reports medically significant (important) adverse events or exposure to COVID-19 vaccines during pregnancy or periconception period. As of February 14, 2022, there have been over 201,000 pregnancies reported in CDC’s v-safe after-vaccination health checker.
    • Vaccine Adverse Event Reporting System (VAERS): A national early warning system to detect possible safety problems in U.S.-licensed vaccines. VAERS is co-managed by the CDC and the FDA. Healthcare professionals are encouraged to report any clinically significant adverse events following vaccination to VAERS, even if they are not sure if vaccination caused the event. In addition, we are anticipating that the following adverse events will be required to be reported to VAERS for COVID-19 vaccines administered under an EUA:
      • Vaccine administration errors (whether associated with an adverse event or not)
      • Serious adverse events (irrespective of attribution to vaccination) (such as death, life-threatening adverse event, inpatient hospitalization)
      • Multisystem inflammatory syndrome (MIS) in children (if vaccine is authorized in children) or adults
      • Cases of COVID-19 that result in hospitalization or death
    • CDC’s National Healthcare Safety Network (NHSN): An acute-care and long-term care facility monitoring system with reporting to VAERS
    • Vaccines and Medications in Pregnancy Surveillance System (VAMPSS): A national surveillance system designed to monitor the use and safety of vaccines and asthma medications during pregnancy
    • FDA is working with large insurer/payer databases on a system of administrative and claims-based data for surveillance and research
    • Additional safety monitoring information can be found at https://www.cdc.gov/coronavirus/2019-ncov/vaccines/safety.html.

Additional Resources


References

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  41. Prabhu M, Murphy EA, Sukhu AC, Yee J, Singh S, Eng D, et al. Antibody response to coronavirus disease 2019 (COVID-19) messenger RNA vaccination in pregnant women and transplacental passage into cord blood [published online April 28, 2021]. Obstet Gynecol. DOI: 10.1097/AOG.0000000000004438. Available at: https://journals.lww.com/greenjournal/Fulltext/9900/Antibody_Response_to_Coronavirus_Disease_2019.184.aspx. Retrieved June 4, 2021.
  42. Ruderman RS, Mormol J, Trawick, E, et al. Association of COVID-19 Vaccination During Early Pregnancy with Risk of Congenital Fetal Anomalies. JAMA Pediatr. Published online April 04, 2022. doi:10.1001/jamapediatrics.2022.01642022.
  43. Schlake T, Thess A, Fotin-Mleczek M, Kallen KJ. Developing mRNA-vaccine technologies. RNA Biol. 2012;9(11):1319-1330. doi:10.4161/rna.22269. U.S. Food and Drug Administration. December 11, 2020 communication to Pfizer Inc. Available at: https://www.fda.gov/media/144412/download. Retrieved December 13, 2020.
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  46. Shimabukuro TT, Kim SY, Myers TR, Moro PL, Oduyebo T, Panagiotakopoulos L, et al. Preliminary findings of mRNA Covid-19 vaccine safety in pregnant persons. CDC v-safe COVID-19 Pregnancy Registry Team [published online April 21, 2021]. N Engl J Med. DOI: 10.1056/NEJMoa2104983. Available at: https://www.nejm.org/doi/10.1056/NEJMoa2104983. Retrieved April 27, 2021.
  47. Stock SJ, Carruthers J, Calvert C, Denny C, Donaghy J, Goulding A, et al. SARS-CoV-2 infection and COVID-19 vaccination rates in pregnant women in Scotland. Nat Med. Published online January 13, 2022. doi: 10.1038/s41591-021-01666-2.
  48. U.S. Food and Drug Administration. Fact sheet for healthcare providers administering vaccine (vaccination providers). Emergency Use Authorization (EUA) of the Pfizer-Biontech COVID-19 vaccine to prevent Coronavirus Disease 2019 (COVID-19). Available at: https://www.fda.gov/media/144413/download. Retrieved December 13, 2020.
  49. U.S. Food and Drug Administration. Fact Sheet for Recipients and Caregivers. Emergency Use Authorization (EUA) of the Pfizer-Biontech COVID-19 vaccine to prevent Coronavirus Disease 2019 (COVID-19) in individuals 16 years of age and older. Available at: https://www.fda.gov/media/144414/download. Retrieved December 13, 2020.
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  61. Yang YJ, Murphy EA, Singh S, Sukhu AC, Wolfe I, Adurty S, et al. Association of gestational age at coronavirus disease 2019 (COVID-19) vaccination, history of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, and a vaccine booster dose with maternal and umbilical cord antibody levels at delivery. Obstet Gynecol. Published online December 28, 2021. doi: 10.1097/AOG.0000000000004693.
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  63. Zambrano LD, Ellington S, Strid P, Galang RR, Oduyebo T, Tong VT, et al. Update: characteristics of symptomatic women of reproductive age with laboratory-confirmed SARS-CoV-2 infection by pregnancy status – United States, January 22-October 3, 2020. CDC COVID-19 Response Pregnancy and Infant Linked Outcomes Team. MMWR Morb Mortal Wkly Rep 2020;69:1641-7. Available at: https://www.cdc.gov/mmwr/volumes/69/wr/mm6944e3.htm. Retrieved December 11, 2020.
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A Practice Advisory is a brief, focused statement issued to communicate a change in ACOG guidance or information on an emergent clinical issue (e.g., clinical study, scientific report, draft regulation). A Practice Advisory constitutes ACOG clinical guidance and is issued only on-line for Fellows but may also be used by patients and the media. Practice Advisories are reviewed periodically for reaffirmation, revision, withdrawal or incorporation into other ACOG guidelines.

This information is designed as an educational resource to aid clinicians in providing obstetric and gynecologic care, and use of this information is voluntary. This information should not be considered as inclusive of all proper treatments or methods of care or as a statement of the standard of care. It is not intended to substitute for the independent professional judgment of the treating clinician. Variations in practice may be warranted when, in the reasonable judgment of the treating clinician, such course of action is indicated by the condition of the patient, limitations of available resources, or advances in knowledge or technology. The American College of Obstetricians and Gynecologists reviews its publications regularly; however, its publications may not reflect the most recent evidence. Any updates to this document can be found on www.acog.org or by calling the ACOG Resource Center.

While ACOG makes every effort to present accurate and reliable information, this publication is provided “as is” without any warranty of accuracy, reliability, or otherwise, either express or implied. ACOG does not guarantee, warrant, or endorse the products or services of any firm, organization, or person. Neither ACOG nor its officers, directors, members, employees, or agents will be liable for any loss, damage, or claim with respect to any liabilities, including direct, special, indirect, or consequential damages, incurred in connection with this publication or reliance on the information presented.

COVID-19 booster shot can cause irregular menstrual periods – Health Ministry

Women and young people are more susceptible to experiencing the side effects of the booster shot, a Health Ministry study showed.

Authors: JERUSALEM POST STAFF Published: FEBRUARY 9, 2022 16:52

Some 10% of Israeli women experienced irregular menstrual periods after receiving the COVID-19 booster shot, a new Health Ministry study on the side effects of the third vaccine published on Wednesday shows.

The Health Ministry study sought to examine the prevalence of symptoms developed 21 to 30 days after receiving Pfizer’s booster vaccine.

Women and young people are more susceptible to experiencing the side effects of the booster shot, the study showed. Additionally, the most common symptom reported in the study is irregular menstruation, with 10% of women up to the age of 54 who participated in the study reporting to have experienced the side effect. 

The study found that most side effects reported were extremely mild and passed after three days at the most.

In addition, neurological and allergic reactions were found to be much less common than with previous COVID-19 vaccines as only 4% reported to have experienced such reactions to the vaccine. However, the minority who have experienced allergic and neurological reactions reported having experienced such effects after a longer period of time.

Overall, the study found that most of the symptoms reported by the participants were less severe compared to previous vaccines.

Some 2,049 Israelis over the age of 18 participated in the study, with an almost even split of males (51%) and females (49%). The Health Ministry examined the side effects for three different age groups (18-39, 40-59, 60+).

Association Between Menstrual Cycle Length and Coronavirus Disease 2019 (COVID-19) Vaccination

A U.S. Cohort

Authors: Edelman, Alison MD, MPH; Boniface, Emily R. MPH; Benhar, Eleonora PhD; Han, Leo MD, MPH; Matteson, Kristen A. MD, MPH; Favaro, Carlotta PhD; Pearson, Jack T. PhD; Darney, Blair G. PhD, MPH

Obstetrics & Gynecology: January 5, 2022 – Volume – Issue – 10.1097/AOG.0000000000004695doi: 10.1097/AOG.0000000000004695

OBJECTIVE: 

To assess whether coronavirus disease 2019 (COVID-19) vaccination is associated with changes in cycle or menses length in those receiving vaccination as compared with an unvaccinated cohort.

METHODS: 

We analyzed prospectively tracked menstrual cycle data using the application “Natural Cycles.” We included U.S. residents aged 18–45 years with normal cycle lengths (24–38 days) for three consecutive cycles before the first vaccine dose followed by vaccine-dose cycles (cycles 4–6) or, if unvaccinated, six cycles over a similar time period. We calculated the mean within-individual change in cycle and menses length (three prevaccine cycles vs first- and second-dose cycles in the vaccinated cohort, and the first three cycles vs cycles four and five in the unvaccinated cohort). We used mixed-effects models to estimate the adjusted difference in change in cycle and menses length between the vaccinated and unvaccinated cohorts.

RESULTS: 

We included 3,959 individuals (vaccinated 2,403; unvaccinated 1,556). Most of the vaccinated cohort received the Pfizer-BioNTech vaccine (55%) (Moderna 35%, Johnson & Johnson/Janssen 7%). Overall, COVID-19 vaccine was associated with a less than 1-day change in cycle length for both vaccine-dose cycles compared with prevaccine cycles (first dose 0.71 day-increase, 98.75% CI 0.47–0.94; second dose 0.91, 98.75% CI 0.63–1.19); unvaccinated individuals saw no significant change compared with three baseline cycles (cycle four 0.07, 98.75% CI −0.22 to 0.35; cycle five 0.12, 98.75% CI −0.15 to 0.39). In adjusted models, the difference in change in cycle length between the vaccinated and unvaccinated cohorts was less than 1 day for both doses (difference in change: first dose 0.64 days, 98.75% CI 0.27–1.01; second dose 0.79 days, 98.75% CI 0.40–1.18). Change in menses length was not associated with vaccination.

CONCLUSION: 

Coronavirus disease 2019 (COVID-19) vaccination is associated with a small change in cycle length but not menses length.

Concerns about a possible association between coronavirus disease 2019 (COVID-19) vaccination and abnormal menstrual cycles may lead to vaccine hesitancy. Unfortunately, clinical trials of the current COVID-19 vaccines did not collect menstrual cycle outcomes postvaccine.1–4 VAERS (Vaccine Adverse Event Reporting System) does not actively collect information regarding menstrual cycles, and, by May 2021, only a small number of individuals (fewer than 200) had self-reported a menstrual-related issue to VAERS.5 Social media reports suggest menstrual disturbances are much more common but that these disturbances appear to be temporary.6,7 The lack of population-level, prospective evidence about the relationship of COVID-19 vaccination and menstrual cycles limits our ability to sufficiently address these concerns and to counsel individuals who menstruate about what to expect with vaccination.

Menstrual cyclicity is an overt sign of health and fertility. Menstrual characteristics are not static, and variability exists month to month across an individual’s lifespan.8–10 The International Federation of Gynecology and Obstetrics classifies a variation in cycle length as normal if less than 8 days. Regularly menstruating individuals can also experience sporadic or stress-induced ovulation perturbances, which may result in a skipped cycle or a temporary change in cycle length.11–14 This normal variability may be perceived as concerning, especially in conjunction with a new exposure such as COVID-19 vaccination.

Here, we present an analysis of prospectively collected menstrual cycle tracking data from U.S. individuals using the U.S. Food and Drug Administration–cleared digital fertility-awareness application “Natural Cycles” to assess whether COVID-19 vaccination is associated with changes in cycle or menses length during the menstrual cycles when vaccine doses are received.

METHODS

We conducted a retrospective cohort analysis of menstrual cycle data that were collected prospectively. Cycle data ranged from October 2020 to September 2021, with initial COVID-19 vaccine doses administered between December 2020 and July 2021. Individuals who use the digital fertility-awareness application Natural Cycles voluntarily choose to prospectively track physiologic data related to their menstrual cycles for purposes of nonhormonal pregnancy prevention or planning and consent to the use of their de-identified data for research (consent can be removed if desired). A detailed description of variables tracked by the application has been published elsewhere.10 We included U.S. residents aged 18–45 years who were at least three cycles postpregnancy or postuse of hormonal contraception. Included individuals had normal prevaccination menstrual cycle lengths (average 24–38 days).8 Each individual contributed six consecutive cycles of data. For those who received a COVID-19 vaccination, we included three prevaccine cycles and three post–first vaccine dose, inclusive of the vaccination cycle. We included six consecutive cycles for those who remained unvaccinated. Included vaccine types were Pfizer-BioNTech (Pfizer), Moderna, Johnson & Johnson/Janssen [J&J/Janssen], and unspecified. We excluded menopausal individuals and those who received the Oxford/AstraZeneca vaccine to focus on U.S. Food and Drug Administration–approved, U.S.-available vaccines.

The primary exposure was COVID-19 vaccination status as reported by individuals using the Natural Cycles application. Prompted by in-application messages from Natural Cycles, individuals logged their vaccination date(s) or confirmed their unvaccinated status. Individuals without confirmed vaccination information were not included in the data set.

Our primary outcome was the within-individual change in cycle length (in days) from the three-cycle prevaccination average to the initial vaccination cycle. For vaccinated individuals, cycle four was the first vaccine-dose cycle; the cycle of the second dose varied based on when the second vaccine dose occurred (cycle four, five, or six). For the unvaccinated cohort, we designated cycle four as the artificial first vaccine-dose cycle and cycle five as the artificial second-dose cycle; cycles one, two, and three were considered the equivalent of prevaccination cycles. Secondary outcomes were the same within-individual change in cycle length for the second vaccination cycle and corresponding changes in menses length for the first and second vaccine-dose cycles. We also examined the proportion of participating individuals who experienced a clinically significant change in cycle length (8 days or more).

Additional sociodemographic information was collected to further characterize the cohort. Of note, individuals using the Natural Cycles application are required to log only their age; logging other sociodemographic information is voluntary. Missingness was nonignorable and was included as a category in analyses. We categorized age at the start of the first cycle as 18–24, 25–29, 30–34, 35–39, or 40–45 years. Race and ethnicity were reported as Asian, Black, Hispanic, Middle Eastern or North African, Native Hawaiian or Pacific Islander, or White, which we collapsed into a binary variable for modeling owing to small sample sizes for some groups. We classified state of residence into Census regions: Northeast, Midwest, South, or West. Additional characteristics included parity (nulliparous vs parous), body mass index (BMI [calculated as weight in kilograms divided by height in meters squared]: underweight or normal weight, overweight, or obese), education (at least a 4-year college degree or not), and relationship status (in a steady relationship or not).

We had more than 99% power to detect an unadjusted 1-day difference in cycle length change or 0.5-day difference in menses length change by vaccination status, at a significance level of 0.0125 (98.75% CIs), to account for multiple comparisons among the four main outcomes: cycle and menses length for the first and second vaccine-dose cycles.

The Oregon Health & Science University Institutional Review Board approved the protocol. De-identified data were used under a data-use agreement with Natural Cycles USA Corp (New York, New York) and from the Reading Independent Ethics Committee (Reading, United Kingdom).

We compared within-individual changes in cycle and menses length between the three prevaccination–cycle average and the first- and second-dose vaccination cycles, or with cycle four and five for the unvaccinated participants, using two-sided t tests. We created histograms overlaying vaccination status to compare the distributions of changes in cycle and menses length and compared the proportion of individuals who experienced a clinically significant change in cycle length (8 days or more) using Pearson’s χ2 tests. Longitudinal multivariable mixed-effects models were used for all outcomes and plotted the adjusted marginal means. Models contained random intercepts and slopes at the individual level and an interaction term between time (prevaccination and postvaccination) and vaccination status to determine the effect of vaccination, that is, the adjusted difference in the change in cycle and menses length between vaccination groups. All estimates were adjusted for age, race and ethnicity, BMI, education, parity, and relationship status. Census region was not associated with any outcome, did not act as a confounder, and was excluded from models.

As a subanalysis, we separated individuals who received both vaccine doses in one cycle from those who received doses over two cycles. We compared unadjusted within-individual changes in cycle length between the three prevaccination cycles and the vaccine (both doses) cycle. We also compared changes between cycle six and the three prevaccine cycles by vaccination status to test whether any changes observed in the vaccination cycle persisted over time.

We conducted multiple sensitivity analyses to confirm the robustness of our results. First, we compared changes in cycle and menses length by vaccine brand. Second, we excluded individuals with any prevaccination cycle whose absolute cycle length was outside of the 24–38-day range (579 individuals). Third, we excluded any individuals who reported polycystic ovarian syndrome, thyroid disorder, or endometriosis (226 individuals). Fourth, we excluded any individuals who reported use of emergency contraception during at least one study cycle (157 individuals). Finally, although the data did not meet the missing at random assumption required for imputation techniques, we used imputation followed by weighting with covariate balancing propensity scores and bootstrapped SEs to confirm that our results were not biased by missing data.15

RESULTS

Of 10,179 eligible individuals, 3,959 representing 23,754 cycles met inclusion criteria (Fig. 1). The majority of excluded individuals had not tracked a sufficient number of cycles during the study period (4,744 individuals). We excluded 304 individuals with nonconsecutive cycles, 331 with an average prevaccination cycle length outside of the 24–38-day range, and individuals who were less than three cycles post pregnancy (n=109) or post–hormonal contraception use (n=713). We also excluded a small number of individuals outside of the study age range (n=3), who received the Oxford/AstraZeneca vaccine (n=14), or who were menopausal (n=2).

Fig. 1.
Fig. 1.: STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) flow diagram. COVID-19, coronavirus disease 2019.Edelman. COVID-19 Vaccine and Menstrual Health Outcomes. Obstet Gynecol 2022.

The final study sample included 2,403 vaccinated individuals and 1,556 unvaccinated individuals (Table 1). The vaccinated cohort was slightly older (34% 30–34 years of age vs 24% among unvaccinated) and more likely to be nulliparous (79% vs 69%) and college educated (77% vs 60%) as compared with the unvaccinated group. Vaccinated individuals were also more likely to identify as White (54% vs 47%) and to live in the Northeast (20% vs 13%) or West (37% vs 34%) U.S. Census regions. More than half of the vaccinated cohort received the Pfizer Covid-19 vaccine (55%) (Moderna 35%, J&J/Janssen 7%).

Table 1.
Table 1.: Characteristics of the Study Participants (N=3,959)

Overall, the vaccinated cohort experienced a less than 1-day unadjusted increase in the length of their menstrual cycle during the first vaccine cycle compared with their three prevaccination cycles (Table 2, 0.71-day increase, 98.75% CI 0.47–0.94); the unvaccinated cohort had no significant change in cycle four compared with their first three cycles (0.07-day increase, 98.75% CI −0.22 to 0.35). Although statistically significant, the overlaid histograms show a cycle length change distribution in vaccinated individuals that is roughly equivalent to that in unvaccinated individuals (Fig. 2A, left), and the proportion of individuals who experienced a clinically significant change in cycle length of 8 days or more did not differ by vaccination status (4.3% for unvaccinated vs 5.2% for vaccinated, P=.181; data not shown). After adjusting for confounders, the difference in the change in cycle length by vaccination status was 0.64 days (Fig. 2B, left, Table 2, 98.75% CI 0.27–1.01) (see Appendix 1, available online at https://links.lww.com/AOG/C572, for the full model).

Table 2.
Table 2.: Within-Individual Unadjusted Change in Cycle Length and Menses Length From Three Prevaccination–Cycle Average to First or Second Vaccination Cycle and Adjusted Difference in Change Compared With Unvaccinated Individuals
Fig. 2.
Fig. 2.: A. Overlayed histograms of the change in cycle length (days) between the three prevaccination cycle average and the vaccination cycle for first dose (left) or second dose (right). Histograms for unvaccinated individuals are shown in red, vaccinated individuals are shown in blue, and overlapping distributions are shown in purpleB. Adjusted marginal means for cycle length (days) for the three prevaccination cycle average and the vaccination cycle first dose (left) or second dose (right). Estimates are from mixed-effects models with random intercepts and random slopes at the user level, an interaction between vaccination status and prevaccination and postvaccination timing, and adjusted for age, race, body mass index, educational attainment, parity, and relationship status. Unvaccinated individuals are shown in red, and vaccinated individuals are shown in blueerror bars represent 98.75% CIs.Edelman. COVID-19 Vaccine and Menstrual Health Outcomes. Obstet Gynecol 2022.

The majority of vaccinated individuals received a second vaccine dose: 15% in cycle four, 63% in cycle five, and 2% in cycle six (data not shown). This group, which excluded individuals who received the one-dose J&J/Janssen vaccine (7%) or who did not receive a second dose of the Pfizer or Moderna vaccines (13%), experienced an unadjusted mean 0.91-day increase in cycle length during their second vaccine cycle (Fig. 2A, right, Table 2, 98.75% CI 0.63–1.19); unvaccinated individuals had no significant change (0.12 day-increase, 98.75% CI −0.15 to 0.39). During the second vaccine cycle, a slightly higher proportion of participants had a change in cycle length of 8 days or more (4.6% unvaccinated vs 6.5% vaccinated, P=.017), although this difference was not statistically significant at the 0.0125 significance level. After adjusting for confounders, the difference in the change in cycle length for the second vaccine cycle by vaccination status was 0.79 days (Fig. 2B, right, Table 2, 98.75% CI 0.40–1.18).

The increase in cycle length for both the first and second vaccine cycles appears to be driven largely by the 358 individuals who received both vaccine doses within a single cycle (cycle four). This subgroup experienced a 2-day unadjusted mean cycle length increase (Table 3, 2.38 days, 98.75% CI 1.52–3.24), and 10.6% had an increase in cycle length of 8 days or more compared with 4.3% in the unvaccinated cohort (P<.001). When these individuals were removed from the analysis, the unadjusted increases in cycle length for first and second doses in separate cycles were smaller (Table 3) and there were no significant differences in the proportion of individuals with a change in cycle length of 8 days or more compared with unvaccinated individuals (data not shown). In adjusted models, individuals who received both vaccine doses within one cycle experienced a 2-day increase in cycle length compared with unvaccinated individuals (Table 3, difference in change by vaccination status 2.32 days, 98.75% CI 1.59–3.04). The adjusted difference for individuals who received one dose in their first vaccine cycle was no longer significant compared with unvaccinated individuals (difference in change by vaccination status 0.34 days, 98.75% CI −0.01 to 0.70), and the adjusted difference for individuals who received one dose in their second vaccine cycle was also smaller (0.45 days, 98.75% CI 0.06–0.84). These differences do not appear to be driven by individuals with naturally longer cycle lengths; among the 358 individuals who received two doses in a single cycle, just 15 (4%) received their second dose outside of our defined normal cycle length range of 24–38 days (data not shown).

Table 3.
Table 3.: Unadjusted Change in Cycle Length From Three Prevaccination–Cycle Average to Coronavirus Disease 2019 (COVID-19) Vaccination Cycle and Adjusted Difference in Change Compared With Unvaccinated Individuals for First and Second Doses and for Both Doses Received in the Same Cycle

By cycle six, for those who received both vaccine doses in a single cycle (cycle four), the change in cycle length compared with their three prevaccination cycles was no longer different from the changes in the unvaccinated group. Unvaccinated individuals had a nonsignificant change in cycle length from the prevaccination average of 0.24 days (98.75% CI −0.04 to 0.51), and the 358 individuals who received two doses in their first vaccine cycle also had a nonsignificant change of 0.17 days (98.75% CI −0.33 to 0.67).

We found no changes in unadjusted menses length for either the first or second vaccination cycle (Table 2, Appendix 2 [Appendix 2 is available online at https://links.lww.com/AOG/C572]). There were no differences in adjusted menses length changes by vaccination status for either vaccine cycle: first dose 0.08-day difference (98.75% CI −0.04 to 0.19), second dose 0.08-day difference (98.75% CI −0.04 to 0.20) (see Appendix 3, available online at https://links.lww.com/AOG/C572, for full modeling results). Stratification by individuals who received both doses in one cycle did not change results for menses length (data not shown).

Sensitivity analyses comparing the changes in cycle and menses length by vaccine brand, excluding those with more variable prevaccination cycle lengths, gynecologic disorders, or emergency contraception use, and imputation and sample weighting did not alter our results in a clinically meaningful way (see Appendices 4 and 5, available online at https://links.lww.com/AOG/C572, for imputation and weighting results).

DISCUSSION

We evaluated 23,754 menstrual cycles prospectively reported by 3,959 U.S. individuals to evaluate whether COVID-19 vaccination is associated with menstrual cycle disturbances during cycles when vaccination occurs. After adjusting for confounders, we found that normally cycling individuals experienced small variations in cycle length regardless of vaccination status. Statistically significant differences existed between vaccination status groups, but the change in cycle length was less than 1 day, which is below the reportable difference in the menstrual cycle tracking application and is not clinically significant. A subset of individuals who received both vaccine doses in a single cycle had, on average, an adjusted 2-day increase in their vaccination cycle length compared with unvaccinated individuals. Although approximately 10% of these individuals experienced a clinically notable change in cycle length of 8 days or more, this change attenuated quickly within two postvaccine cycles. We found no change in menses length between or within vaccination cohorts.

Menstrual cycle timing is regulated by the hypothalamic-pituitary-ovarian axis, which can be affected by life, environment, and health stressors.11–13,16 Our results cannot be explained by generalized pandemic stress because our unvaccinated control group saw no changes over a similar time period. Our findings are consistent with a recent analysis of 18,076 Natural Cycles application users before and during the pandemic that also demonstrated no population-level cycle timing disruptions due to pandemic stress.17

mRNA vaccines create a robust immune response or stressor, which could temporarily affect the hypothalamic-pituitary-ovarian axis if timed correctly.18–20 Our findings for individuals who received two doses in a single cycle supports this hypothesis. Given the dosing schedule of the mRNA COVID-19 vaccines in the United States (21 days for Pfizer and 28 days for Moderna), an individual receiving two doses in a single cycle would have received the first dose in the early follicular phase. Cycle length variability results from events leading to the recruitment and maturation of the dominant follicle during the follicular phase, processes known to be affected by stress.12,21 In contrast, an acute severe illness with or without septicemia, such as COVID-19, could be catastrophic to hypothalamic-pituitary-ovarian axis function, sometimes permanently.18,22–24

This research directly addresses concerns raised by self-reports through VAERS and public discourse.5–7,25 The types of concerns raised range from cycle and menses length changes to differences in menstrual-associated symptoms, unscheduled bleeding, and changes in the quality and quantity of menstrual bleeding.6 Self-reports are useful for rapidly identifying potential signals or rare adverse events, but they are limited by significant confounding and reporting biases. Our study strengths include prospectively collected menstrual cycle data, which limits recall bias, a control group of unvaccinated individuals, and adjustment for sociodemographic factors associated with vaccination status and menstrual cycle changes (eg, age, BMI). Our sample size is also sufficiently large to identify small differences, even 1 day, in cycle and menses length that may be of interest to individuals but might not rise to the level of clinical concern (8 days or more) or trigger a medical evaluation for secondary amenorrhea (no menses for 3 months).8,26 However, for an individual, small cycle changes can cause concern or raise hopes, especially if avoiding or planning for pregnancy, and this level of detail will likely be valuable.

Our study also has limitations. First, it may not be generalizable to the U.S. population given the selection of Natural Cycles users (more likely to be White, college educated, and have lower BMIs than national distributions and not using hormonal contraception). Second, we also chose to analyze a cohort with consistent normal cycle lengths to clearly identify any associations between cycle and menses length and COVID-19 vaccination. We recognize that many individuals who menstruate do not fit into this normal category.8,10 Other subpopulations are known to have greater baseline variations in menstrual cyclicity, such as individuals with BMIs higher than 35. We do not yet know whether these populations experience greater changes in cycle and menses length in association with COVID-19 vaccination. Third, although our results suggest that individuals receiving two doses in a single cycle return to baseline cycle length quickly, our data do not yet include enough subsequent cycles without vaccine to investigate this fully for the entire vaccinated cohort. Finally, we do not have data on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in either our vaccinated or unvaccinated groups.

Our findings are reassuring; we find no population-level clinically meaningful change in menstrual cycle length associated with COVID19 vaccination. Our findings support and help explain the self-reports of changes in cycle length. Individuals receiving two COVID-19 vaccine doses in a single cycle do appear to experience a longer but temporary cycle length change. Coronavirus disease 2019 (COVID-19) vaccination is not associated with changes in menses length. Questions remain about other possible changes in menstrual cycles, such as menstrual symptoms, unscheduled bleeding, and changes in the quality and quantity of menstrual bleeding.

REFERENCES

1. Polack FP, Thomas SJ, Kitchin N, Absalon J, Gurtman A, Lockhart S, et al. Safety and efficacy of the BNT162b2 mRNA covid-19 vaccine. New Engl J Med 2020;383:2603–15. doi: 10.1056/NEJMoa2034577

2. Oliver SE, Gargano JW, Marin M, Wallace M, Curran KG, Chamberland M, et al. The Advisory Committee on Immunization Practices’ interim recommendation for use of Moderna COVID-19 vaccine — United States, December 2020. MMWR Morb Mortal Wkly Rep 2021;69:1653–6. doi: 10.15585/mmwr.mm695152e1

3. Sadoff J, Gray G, Vandebosch A, Cárdenas V, Shukarev G, Grinsztejn B, et al. Safety and efficacy of single-dose Ad26.COV2.S vaccine against covid-19. New Engl J Med 2021;384:2187–201. doi: 10.1056/NEJMoa2101544View full references list

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NIH orders $1.67M study on how COVID-19 vaccine impacts menstrual cycle

Authors: By Hannah Sparks September 7, 2021

The National Institutes of Health has announced a $1.67 million study to investigate reports that suggest the COVID-19 vaccine may come with an unexpected impact on reproductive health.

It’s been a little over six months since the three COVID-19 vaccines in the US — Pfizer, Moderna and Johnson & Johnson — became widely available to all adults. But even in the early days of vaccine rollout, some women were noticing irregular periods following their shots, as reported first by the Lily in April.

Shana Clauson, 45, spoke to the Washington Post’s women’s news site at the time, and again this week, about her experience after getting the jab — revealing that her period arrived earlier and heavier than what she considers normal. She was one of many who gathered on social media to share what they were seeing.

“Is this not being discussed, or is it even being looked at or researched because it’s a ‘woman’s issue?’ ” Clauson speculated to the Lily last spring.

Women, those under 40 more likely to have side effects to COVID vaccine, expert says

It would appear that the NIH heard Clauson and others’ reports, as they announced on Aug. 30 that they intended to embark on just such research — aiming to incorporate up to half a million participants, including teens and transgender and nonbinary people.

Researchers at Boston University, Harvard Medical School, Johns Hopkins University, Michigan State University and Oregon Health and Science University have been enlisted to embark on the study, commissioned by the NIH’s National Institute of Child Health and Human Development (NICHD) and the Office of Research on Women’s Health.

The approximately yearlong study will follow initially unvaccinated participants to observe changes that occur following each dose. More specifically, some groups will exclude participants on birth control or gender-affirming hormones, which may have their own impact on periods.

“Our goal is to provide menstruating people with information, mainly as to what to expect, because I think that was the biggest issue: Nobody expected it to affect the menstrual system, because the information wasn’t being collected in the early vaccine studies,” said NICHD director Diana Bianchi in a statement to the Lily — reportedly crediting their early coverage for helping to make the NIH aware.

‘We were worried this was contributing to vaccine hesitancy in reproductive-age women.’

NICHD director Diana Bianchi

The NIH suggests that changes to the menstrual cycle could arise out of several of life’s circumstances during a pandemic — the stress of lifestyle changes or possibly contending with illness. Moreover, the immune and reproductive systems are intrinsically linked, and the notion that the immune-boosting vaccine may disrupt the typical menstrual cycle is plausible, as demonstrated by previous studies concerning vaccine uptake.

It’s also worth noting the vaccine does not cause infertility and the Centers for Disease Control and Prevention recommends the shot even for pregnant women.

As changes to the menstrual cycle are “really not a life and death issue,” explained Bianchi, the Food and Drug Administration — fast-tracking their work — prioritized only the most critical risks associated with the COVID-19 vaccine.

The NIH, too, pulled together the initiative at breakneck speed. Funding for such a study would typically take years to see approval.

“We were worried this was contributing to vaccine hesitancy in reproductive-age women,” said Bianchi.

Biden team’s misguided and deadly COVID-19 vaccine strategy

Vaccination ‘arms race’ could prove dangerous to the American public

Authors: Dr. Robert Malone and Peter Navarro

The Biden administration’s strategy to universally vaccinate in the middle of the pandemic is bad science and badly needs a reboot.

This strategy will likely prolong the most dangerous phase of the worst pandemic since 1918 and almost assuredly cause more harm than good – even as it undermines faith in the entire public health system.

Four flawed assumptions drive the Biden strategy. The first is that universal vaccination can eradicate the virus and secure economic recovery by achieving herd immunity throughout the country (and the world).  However, the virus is now so deeply embedded in the world population that, unlike polio and smallpox, eradication is unachievable. SARS-CoV-2 and its myriad mutations will likely continually circulate, much like the common cold and influenza.

The second assumption is that the vaccines are (near) perfectly effective. However, our currently available vaccines are quite “leaky.” While good at preventing severe disease and death, they only reduce, not eliminate, the risk of infection, replication, and transmission. As a slide deck from the Centers for Disease Control has revealed, even 100% acceptance of the current leaky vaccines combined with strict mask compliance will not stop the highly contagious Delta variant from spreading.

The third assumption is that the vaccines are safe.  Yet scientists, physicians, and public health officials now recognize risks that are rare but by no means trivial.  Known side effects include serious cardiac and thrombotic conditions, menstrual cycle disruptions, Bell’s Palsy, Guillain Barre syndrome, and anaphylaxis.

Unknown side effects which virologists fear may emerge include existential reproductive risks, additional autoimmune conditions, and various forms of disease enhancement, i.e., the vaccines can make people more vulnerable to reinfection by SARS-CoV-2 or reactivation of latent viral infections and associated diseases such as shingles.  With good reason, the FDA has yet to approve the vaccines now administered under Emergency Use Authorization.

The failure of the fourth “durability” assumption is the most alarming and perplexing.  It now appears our current vaccines are likely to offer a mere 180-day window of protection – a decided lack of durability underscored by scientific evidence from Israel and confirmed by  Pfizer, the Department of Health and Human Services, and other countries. 

For More Information: https://www.washingtontimes.com/news/2021/aug/5/biden-teams-misguided-and-deadly-covid-19-vaccine-/

OBGYN explains why a COVID vaccine might affect menstrual cycles

Authors: Kate Larsen

SAN FRANCISCO — Anecdotal evidence from women around the country has led to questions about how COVID-19 vaccines may affect women’s menstrual cycles.

When ABC7 News reporter, Kate Larsen, posted the question on social media, it became clear that a lot of women are experiencing cycle changes, and are wondering if it’s related to the vaccine.

Women wrote:

“I had my 1st COVID-19 vaccine in January followed by the 2nd in February, and since then I have had hemorrhagic bleeding with clots. This month of April was the heaviest.”

“I thought I was going crazy, and even went as far as making a doctor’s appt and switching out my BC because mine is so heavy now and its been a month straight”

“I received the Moderna vaccine in January and February I didn’t get my period for 3 months they did multiple blood test, pregnancy test and ultrasounds but everything came back normal. Then finally on April 4 I got my period and it’s been super heavy for the past 22 days non-stop.”

And some women are reporting other changes: “My period has been the lightest in years for the past 2 cycles. Was beginning to wonder if I was pushed into pre-menopause. Also my PMS symptoms haven’t been as bad from what I can tell.”

For More Information: https://abc7ny.com/menstrual-cycles-and-covid-vaccine-side-effects-women-coronavirus-period/10552668/