Should Pregnant And Breastfeeding Women Get Vaccinated Against COVID-19

As of February 26th, COVID-19 cases have reached 113M worldwide and 28.4M in the United States. In an effort to halt its spread and mitigate the devastating economic and psychological toll of COVID-19, the FDA has issued Emergency Use Authorization (EUA) for two vaccines. 

On December 11th, the first COVID-19 vaccine, manufactured by Pfizer and BioNTech, was granted Emergency Use Authorization by the FDA after a successful 95 percent efficacy rate following the completed Phase 3 of its clinical trials. Shortly thereafter, Moderna announced its successful phase 3 clinical trials with an efficacy rate of 94.1 percent and also received FDA Emergency Use Authorization. 

The Center for Disease Control and Prevention (CDC) and the Advisory Committee on Immunization Practices (ACIP) have issued guidelines and recommendations on who should be included as part of the first groups to be vaccinated. Healthcare and essential workers are prioritized to receive the early rounds of vaccines, along with “people of all ages with comorbid and underlying conditions that put them at significantly higher risk & older adults living in congregate or overcrowded settings” like nursing homes and assisted living facilities.
Amongst the population at risk are pregnant women; unfortunately, at this time, many questions remain unanswered in regards to the benefits outweighing the risk of vaccination. Medical authorities and governmental agencies such as the CDC, The American College of Obstetrics and Gynecologists (ACOG), the World Health Organization (WHO), and The Academy of Breastfeeding Medicine have issued their recommendations for pregnant and breastfeeding women after reviewing the main questions below:

  • What are the effects of a COVID -19 infection on pregnancy?
  • What is the current data about the safety of COVID-19 vaccines for women who are pregnant or breastfeeding?
Pregnancy & Coronavirus

What Are the Effects of a COVID-19 Infection on Pregnancy?

The latest information available from the CDC is that “observational data demonstrate that while the absolute risk is low, pregnant people with COVID-19 have an increased risk of severe illness, including illness resulting in intensive care admission, mechanical ventilation, or death. Additionally, they might be at an increased risk of adverse pregnancy outcomes, such as preterm birth” (defined as a birth that would occur before the 37th week of pregnancy).

Furthermore, the CDC has also gathered data from 20 participating jurisdictions in the U.S. on the reporting of birth and infant outcomes as of January 2021. Data on completed pregnancies were collected from 9,383 women, but the timing of infection was only available for 6,313 (67.3%). Of the 9,545 reported birth outcomes among women with COVID-19, 9,466 were live births, and 79 were pregnancy losses. Among the number of women who had live births, 6,489 were to term (37 weeks and over), and 896 births were considered preterm (before 37 weeks).
In November of last year, the CDC revealed that pregnant women with COVID-19 ages 35 to 44 years old were nearly four times as likely to require invasive ventilation and twice as likely to die than were non-pregnant women of the same age.

Please keep in mind, as you are reading those alarming probabilities, that “All pregnancies have a risk of birth defect, loss, or other adverse outcomes. In the US general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively,” as clearly announced in the latest Pfizer’s Fact sheet.

On an optimistic note, an article by ACOG revealed that although CDC data states an increased risk of severe outcomes in pregnant women with symptomatic SARS-CoV-2 infection, the absolute risk is still substantially lower than that of pandemic H1N1 influenza infection during pregnancy.

COVID-19 Vaccination

What is the Current Data About the Safety of COVID-19 Vaccines for Women Who Are Pregnant?

Vaccines currently available under the EUA have not been tested on pregnant or lactating women. As clearly expressed on the latest Fact sheet from Pfizer’s vaccine, “Available data on Pfizer-BioNTech COVID-19 Vaccine administered to pregnant women are insufficient to inform vaccine-associated risks in pregnancy,” and “Lactation risk data are not available to assess the effects of Pfizer-BioNTech COVID-19 Vaccine on the breastfed infant or on milk production/excretion.”
During the early phases of the trial, Pfizer and Moderna were very careful NOT to include any pregnant or lactating woman and made sure to impose strict contraceptive measures as part of their inclusion criteria.  People mistakenly understood this as some kind of “proof” that the COVID-19 vaccine may affect fertility or have some teratogenic effect. That is not the case. The reason to exclude women of childbearing age and make sure that there are strict contraceptive methods in place is part of an ethical and safety protocol. “Pregnant people are frequently excluded from drug trials, in part due to understandable concerns about exposing unborn babies to potentially harmful substances.”

According to the CDC’s latest publication, “There are currently few data on the safety of COVID-19 vaccines, including mRNA vaccines, in pregnant people. Limited data are currently available from animal developmental and reproductive toxicity studies. No safety concerns were demonstrated in rats that received the Moderna COVID-19 vaccine prior to or during gestation in terms of female reproduction, fetal/embryonal development, or postnatal development. Studies in pregnant people are planned, and the vaccine manufacturers are following outcomes in people in the clinical trials who became pregnant. Based on current knowledge, experts believe that mRNA vaccines are unlikely to pose a risk to the pregnant person or the fetus because mRNA vaccines are not live vaccines. The mRNA in the vaccine is degraded quickly by normal cellular processes and does not enter the nucleus of the cell. However, the potential risks of mRNA vaccines to the pregnant person and the fetus are unknown because these vaccines have not been studied in pregnant people.”

In spite of the lack of safety data; because of the science behind the mechanism of action of the vaccine along with preliminary results on animal testing and early trials, safety failing to prove any “real concern” have prompted the CDC to leave the choice to pregnant women on whether they should be vaccinated or not by weighing out the benefit/risk balance on a case-per-case basis with their healthcare practitioner:

“If pregnant people are part of a group that is recommended to receive a COVID-19 vaccine (e.g., healthcare personnel), they may choose to be vaccinated. A conversation between the patient and their clinical team may assist with decisions regarding the use of a mRNA COVID-19 vaccine.
When making a decision, pregnant people and their healthcare providers should:

  • consider the level of COVID-19 community transmission,
  • the patient’s personal risk of contracting COVID-19,
  • the risks of COVID-19 to the patient and potential risks to the fetus,
  • the efficacy of the vaccine, the side effects of the vaccine, and the lack of data about the vaccine during pregnancy.”

Another important factor to keep in mind is that “Side effects can occur with COVID-19 vaccine use in pregnant people, similar to those expected among non-pregnant people.” The label update: Effective 1/25/21 on the Fact Sheet for Healthcare Providers Administering Vaccine has been updated to include the additional language, “Severe allergic reactions, including anaphylaxis, have been reported following the Pfizer-BioNTech COVID-19 Vaccine during mass vaccination outside of clinical trials.” Furthermore, “If a pregnant woman experiences a mild reaction like fever following vaccination, she can be “counseled to take acetaminophen because fever has been associated with adverse pregnancy outcomes.”
Although during the early clinical phases of the trial, pregnancy was excluded and strict contraceptive methods were in place, “There is no recommendation for routine pregnancy testing before receipt of a COVID-19 vaccine. Those who are trying to become pregnant do not need to avoid pregnancy after mRNA COVID-19 vaccination.”

Endorsing the CDC’s recommendations, “ACOG recommends that COVID-19 vaccines should not be withheld from pregnant individuals who meet criteria for vaccination based on ACIP-recommended priority groups. While safety data on the use of COVID-19 vaccines in pregnancy are not currently available, there are also no data to indicate that the vaccines should be contraindicated, and no safety signals generated from Developmental and Reproductive Toxicity (DART) studies for the Pfizer-BioNtech and Moderna COVID-19 vaccines. In the interest of patient autonomy, ACOG recommends that pregnant individuals be free to make their own decision regarding COVID-19 vaccination.”

And to that end, ACOG has published a detailed “COVID-19 Vaccines and Pregnancy: Conversation Guide for Clinicians,” going over all the aspects to address during the decision-making process weighing out the benefits versus risks for each individual.

Topics of discussion include the “Risk of COVID-19 Infection During Pregnancy; Safety of COVID-19 Vaccines; Efficacy of COVID-19 Vaccines; Pregnant Patient’s Individual Risk Based on Circumstances; Safety and Efficacy for the Newborn; Special Considerations for Communities of Color and the Continued Support” with all the preventive measures in place.

Additionally, there appears to be anecdotal evidence to suggest that the new COVID-19 variants may be more dangerous to pregnant women. The increase in fatal outcomes in pregnant women due to the new variants may tip the scale in favor of vaccination because the increased benefits may clearly outweigh the risks.   Ultimately, this could lead more pregnant women to get preemptive vaccination against COVID-19. But, what of breastfeeding mothers?

What is the Current Data About the Safety of COVID-19 Vaccines for Women Who Are Breastfeeding?

CDC recommendations on breastfeeding mothers are the same. Although “there are no data on the safety of COVID-19 vaccines in lactating people or the effects of mRNA COVID-19 vaccines on the breastfed infant or milk production/excretion. mRNA vaccines are not thought to be a risk to the breastfeeding infant. A lactating person who is part of a group recommended to receive a COVID-19 vaccine (e.g., healthcare personnel) may choose to be vaccinated.”

A recent study suggests that COVID-19 antibodies can be transferred from an expectant mother to her baby and that early vaccination may provide the fetus with protection via the placenta. However, it is still unclear if the number of antibodies that are transferred to a baby is enough to prevent newborns from getting Covid-19. Further research is needed to determine whether these study results can be replicated in additional trials. During the IAS COVID-19 Conference: Prevention discussions in early February, Dr. Anthony Fauci estimated that “about 10,000 pregnant women in the U.S. have been vaccinated since the Food and Drug Administration authorized two vaccines, and- so far- there have been “no red flags.”

Pregnancy and breastfeeding are very distinct in regards to the risks involved and how a mother’s exposure might transpire or affect her baby. The Academy of Breastfeeding notes: “There are no clinical data regarding the safety of this vaccine in nursing mothers. However, there is little biological plausibility that the vaccine will cause harm, and antibodies to SARS-CoV-2 in milk may protect the breastfeeding child.” Additionally, according to the CDC Advisory Committee on Immunization Practices, except for smallpox and yellow fever, vaccines during lactation do not affect breastfeeding safety for the mother or her child.

In light of such statements and the benefits of breastfeeding in general in the development of a baby’s immunity, the decision on whether to vaccinate lactating mothers might be much more frequent than for pregnant mothers.

In Conclusion

Ultimately, the need for pregnant and lactating women to be included in clinical trials is crucial.  As research continues to progress, and as more women in these categories choose to vaccinate, the implications will be better understood, and the recommendations will be clearer. As for now, the consensus is to allow pregnant and lactating women to get vaccinated following an individually based decision-making process in close partnership with their healthcare practitioner.
Information is evolving rapidly. As new data becomes available, it might be hard to keep track or make sense out of vague and sometimes contradicting publications. Are sources even trustworthy? Unfortunately, not everything posted on the internet can be taken at face value.  In order to make educated decisions, we recommend you regularly visit our blog for the latest information on information published by the CDC, ACOG, WHO, and ACIP.

If you would like to learn more about how umbilical stem cells are being used in the treatment against COVID-19 induced symptoms and about the many current and future benefits of banking your baby’s cord blood and cord tissue stem cells, please join us for an upcoming virtual seminar!
ACOG Patient FAQs: Coronavirus (COVID-19) and Women’s Health Care
ACOG Patient FAQs: Coronavirus (COVID-19), Pregnancy, and Breastfeeding
CDC: Answering Patients’ Questions
CDC: Interim Clinical Considerations for Use of Pfizer-BioNTech COVID-19 Vaccine

Last Updated on: 09/29/2023 by Diane Paradise