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COVID-19 Vaccination Considerations for Obstetric–Gynecologic Care

  • Practice Advisory PA
  • December 2020
 

Last updated August 5, 2022

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 the Novavax COVID-19 vaccine, adjuvanted.

Key Recommendations

  • The American College of Obstetricians and Gynecologists (ACOG) recommends that all eligible persons aged 6 months and older, including pregnant and lactating individuals, receive a COVID-19 vaccine or vaccine series.
  • Messenger RNA (mRNA) and Novavax COVID-19 vaccines are preferred over the Johnson & Johnson/Janssen (J&J/Janssen) COVID-19 vaccine for most individuals, including pregnant and lactating individuals, for primary series.
  • mRNA COVID-19 vaccines are preferred over the J&J/Janssen COVID-19 vaccine for primary additional doses (for immunocompromised persons) and for 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 5 years and older who received an initial mRNA or J&J/Janssen 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 who received Novavax COVID-19 vaccine for their primary series are currently not eligible for a booster. 
  • 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 mRNA COVID-19 vaccines.
    • Novavax is currently not authorized for use as a booster dose.
  • 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, four 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
  • Novavax COVID-19 Vaccine, Adjuvanted

For primary vaccination for all populations, an mRNA or Novavax COVID-19 vaccine series is preferred over the J&J/Janssen COVID-19 vaccine. For booster doses for all populations, an mRNA COVID-19 vaccine is preferred. Individuals who receive Novavax COVID-19 vaccine as their primary series are not currently eligible for a booster dose with any COVID-19 vaccine product.

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 (CDC, Zhang 2019, Schlake 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).

Protein Subunit Vaccines (Novavax Inc.)

Protein subunit vaccines contain pieces (proteins) of the virus that causes COVID-19. These virus pieces are the spike protein. The Novavax COVID-19 Vaccine, Adjuvanted (Novavax COVID-19 vaccine), also contains another ingredient called an adjuvant that helps the immune system respond to that spike protein in the future. Once the immune system knows how to respond to the spike protein, the immune system will be able to respond quickly to the actual virus spike protein and protect against COVID-19. Protein subunit COVID-19 vaccines do not use any live virus nor can they cause infection with the virus that causes COVID-19 or other viruses. They do not affect or interact with our DNA. The protein pieces do not enter the nucleus of the cell where our DNA (genetic material) is located, so they cannot change or influence our genes (CDC).

Protein subunit vaccines have been used for more than 30 years. Other examples of protein subunit vaccines include the first licensed hepatitis B vaccine, some influenza vaccines, and acellular pertussis vaccines.

The Novavax COVID-19 vaccine uses an adjuvant known as Matrix M to boost the immune response against the virus that causes COVID-19. Adjuvants have been used in some vaccines for decades, and limited data on the use of aluminum-containing adjuvants in pregnancy are reassuring (Jamieson, 2012, Rasmussen 2021). Matrix M is a novel adjuvant in COVID-19 vaccines that has had limited study in pregnancy. It is made with saponins, which are naturally occurring in the bark of trees. Similar adjuvants have been used in other vaccines that have reassuring safety profiles in clinical trials. ACOG will continue to monitor data regarding the use of Matrix M adjuvant in COVID-19 vaccines.

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 2021, Prabhu 2021, Juncker 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).

Protein subunit vaccines

On the basis of the results from clinical trials in the U.S., the Novavax COVID-19 vaccine has been shown to be approximately 90% effective overall and 100% effective at preventing severe COVID-19 illness after two doses (ACIP July 2022).

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).

As with other available COVID-19 vaccines, most side effects following the Novavax COVID-19 vaccine were mild. Among study participants aged 18–64 years, less than 1% of individuals receiving a vaccine experienced fever greater than 38 °C following the first dose, and approximately 6% experienced fever following the second dose (FDA 2022). Among study participants aged 65 years or older, less than 0.5% of individuals receiving a vaccine experienced fever greater than 38 °C following the first dose, and 2% experienced fever following the second dose. Overall, the Novavax COVID-19 vaccine may result in fewer systemic side effects than mRNA vaccines (FDA 2022).

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.

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). No cases of anaphylaxis were reported in Novavax COVID-19 vaccine clinical trials (ACIP July 2022).

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 2021, Witberg 2021). Additionally, cases of myocarditis and pericarditis have been identified in clinical trials following the receipt of the Novavax COVID-19 vaccine (7 per 100,000 in the vaccine group) (Novavax 2022). 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).

According to the Provider Fact Sheet for the Novavax COVID-19 vaccine, in a developmental toxicity study, 0.1 mL of a vaccine formulation containing the same quantity of SARS-CoV-2 rS protein (5 micrograms), one-fifth the quantity of adjuvant (10 micrograms), and inactive ingredients that comprise the formulation buffer (25 mM sodium phosphate, 300 mM sodium chloride, and 0.01% (w/v) polysorbate 80) contained in a single dose of the Novavax COVID-19 vaccine was administered to female rats by the intramuscular route on four occasions: 27 and 13 days prior to mating, and on gestational days 7 and 15. No vaccine-related adverse effects on female fertility, fetal development, or postnatal development were reported in the study (FDA Fact Sheet).

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 May 2, 2022, 23,779 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 1.

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 2021, Zauche 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).

Pregnancy was an exclusion criterion for the Novavax COVID-19 vaccine. However, 147 pregnancies were reported during the clinical trial. Of these pregnancies, 56 are ongoing and 41 resulted in a live birth. Additionally, 25 spontaneous abortions (17% of pregnancies, a rate consistent with the general population),13 voluntary terminations, and 1 ectopic pregnancy occurred. No stillbirths have been observed. These data do not indicate a potential risk to the pregnant person or fetus (ACIP July 2022).

Table 1. V-safe Pregnancy Registry Outcomes of Interest in mRNA COVID-19-Vaccinated Pregnant Individuals

Pregnancy Complications* Background Rate V-safe Pregnancy Registry Overall

Gestational diabetes

7–14%

10%

Preeclampsia or gestational hypertension

10–15%

15%

Eclampsia

0.27%

0%

Intrauterine growth restriction

3–7%

1%

Neonatal Outcomes Background Rate V-safe Pregnancy Registry Overall

Preterm birth

8–15%

9.4%

Congenital anomalies

3%

2.2%

Small for gestational age

3.5%

3.2%

Neonatal death

0.38%

0%

*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.

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.

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 6 months 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 CDC for detailed COVID-19 vaccine recommendations by product.

  • mRNA and Novavax COVID-19 vaccines are preferred over J&J/Janssen COVID-19 vaccine for most individuals, including pregnant and lactating individuals, for primary series.
  • mRNA COVID-19 vaccines are preferred over the J&J/Janssen COVID-19 vaccine for 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 6 months and older are only eligible to receive an mRNA vaccine at this time.
    • Novavax COVID-19 vaccine is currently not authorized for use as an additional primary dose or booster dose regardless of the initial vaccine product received.
  • Individuals who receive either the Pfizer-BioNTech, Moderna, or Novavax 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 5 years and older who received an initial mRNA vaccine series or J&J/Janssen COVID-19 vaccine 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 who received Novavax COVID-19 vaccine for their primary series are currently not eligible for a booster.
  • 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 mRNA COVID-19 vaccines.
    • Novavax COVID-19 vaccine is currently not authorized for use as a booster dose.

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. Currently, an additional dose using any COVID-19 vaccine is not authorized for individuals who receive Novavax COVID-19 vaccine as their primary series.

Booster Doses

All individuals aged 5 years and older who received an initial J&J/Janssen COVID-19 vaccine or mRNA 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 who received Novavax COVID-19 vaccine for their primary series are currently not eligible for a booster

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 mRNA COVID-19 vaccines
  • Novavax COVID-19 vaccine is currently not authorized for use as a booster dose

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.

Novavax COVID-19 Vaccine

Currently, a booster dose using any COVID-19 vaccine is not authorized for individuals who receive Novavax COVID-19 vaccine as their primary series.

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 CDC for details.

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 2020, Collin 2020, Delahoy MMWR 2020, Khan 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 2020, Khan 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 2020, Panagiotakopoulos MMWR 2020, Knight 2020, Zambrano MMWR 2020, Allotey 2020, Metz 2021, Galang 2021).

COVID-19 Vaccination

ACOG strongly recommends that pregnant individuals be vaccinated against COVID-19. The mRNA and Novavax COVID-19 vaccines are preferred over the J&J/Janssen COVID-19 vaccine for pregnant individuals, similar to nonpregnant individuals. As of July 16, 2022, about 71% 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 2021, Wainstock 2021, Kachikis 2021, Magnus 2021, Fu 2021, Ruderman 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 who receive Novavax COVID-19 vaccine as their initial vaccine series are currently not eligible for a booster dose.
  • 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 mRNA COVID-19 vaccines.
    • Novavax COVID-19 vaccine is currently not authorized for use as a booster dose, and as stated above, pregnant and recently pregnant people who received Novavax COVID-19 vaccine as their initial vaccine series are currently not eligible for a booster dose.

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 and Novavax 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 2021, Kachikis 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 2021, Young 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, 2021, Morris 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, Moderna, or Novavax), the second dose and booster dose (for mRNA vaccines) should be administered as indicated.

Finally, routine pregnancy testing is not recommended and should not be required prior to receiving any EUA-authorized or FDA-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; 12% of Novavax overall Phase II/III participants were Black and 20% 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 and Novavax COVID-19 vaccine 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 and Novavax COVID-19 vaccines over the J&J/Janssen COVID-19 vaccine 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 and Novavax 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 and Novavax COVID-19 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 the mRNA and Novavax COVID-19 vaccines are preferred, J&J/Janssen COVID-19 vaccines are still available for individuals with a contraindication to mRNA or Novavax COVID-19 vaccines, for persons who would otherwise remain unvaccinated because of limited access to mRNA or Novavax COVID-19 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 and Novavax 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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