As the U.S. races to vaccinate millions of people against the coronavirus, pregnant women face the extra challenge of not knowing whether the vaccines are safe for them or their unborn babies.
None of the recent COVID-19 vaccine trials, including those for Pfizer, Moderna, and Johnson & Johnson, enrolled pregnant or breastfeeding women because they consider them a high-risk group.
That was despite the Society for Maternal-Fetal Medicine and the American College of Obstetricians and Gynecologists asking that pregnant and breastfeeding women be included in trials. The Food and Drug Administration even included pregnant women in the COVID-19 vaccine emergency use authorization (EUA) because of their higher risk of having a more severe disease.
Despite that lack of clinical trial data, more and more smaller studies are suggesting that the vaccines are safe for both mother and child.
Pfizer is now studying its two-dose vaccine in 4,000 pregnant and breastfeeding women to see how safe, tolerated, and robust their immune response is. Researchers will also look at how safe the vaccine is for infants and whether mothers pass along antibodies to children. But the preliminary results won’t be available until the end of the year, a Pfizer spokesperson says.
Without that information, pregnant women are less likely to get vaccinated, according to a large international survey. Less than 45% of pregnant women in the United States said they intended to get vaccinated even when they were told the vaccine was safe and 90% effective. That figure rises to 52% of pregnant women in 16 countries, including the United States, compared with 74% of nonpregnant women willing to be vaccinated. The findings were published online March 1, 2021, in the European Journal of Epidemiology.
The vaccine-hesitant pregnant women in the international study were most concerned that the COVID-19 vaccine could harm their developing fetuses, a worry related to the lack of clinical evidence in pregnant women, said lead researcher Julia Wu, ScD, an epidemiologist at the Harvard School of Public Health’s Human Immunomics Initiative in Boston.
The information vacuum also increases the chances that “people will fall victim to misinformation campaigns like the one on social media that claims that the COVID-19 vaccine causes infertility,” Dr. Wu said. This unfounded claim has deterred some women of childbearing age from getting the vaccine.
Deciding to get vaccinated
Frontline health care professionals were in the first group eligible to receive the vaccine in December 2020. “All of us who were pregnant ... had to decide whether to wait for the data, because we don’t know what the risks are, or go ahead and get it [the vaccine]. We had been dealing with the pandemic for months and were afraid of being exposed to the virus and infecting family members,” said Jacqueline Parchem, MD, a maternal-fetal medicine specialist at the University of Texas Health Science Center, Houston.
Given the lack of safety data, the CDC guidance to pregnant women has been to consult with their doctors and that it’s a personal choice. The Center for Disease Control and Prevention’s latest vaccine guidance said that “there is no evidence that antibodies formed from COVID-19 vaccination cause any problem with pregnancy, including the development of the placenta.”
The CDC is monitoring vaccinated people through its v-safe program and reported on April 12 that more than 86,000 v-safe participants said they were pregnant when they were vaccinated.
Health care workers who were nursing their infants when they were eligible for the vaccine faced a similar dilemma as pregnant women – they lacked the data on them to make a truly informed decision.
“I was nervous about the vaccine side effects for myself and whether my son Bennett, who was about a year old, would experience any of these himself,” said Christa Carrig, a labor and delivery nurse at Massachusetts General Hospital in Boston, who was breastfeeding at the time.
She and Dr. Parchem know that pregnant women with COVID-19 are more likely to have severe illness and complications such as high blood pressure and preterm delivery. “Pregnancy takes a toll on the body. When a woman gets COVID-19 and that insult is added, women who were otherwise young and healthy get much sicker than you would expect,” said Ms. Carrig.
“As a high-risk pregnancy specialist, I know that, with COVID, that babies don’t do well when moms are sick,” said Dr. Parchem.
Pregnant women accounted for more than 84,629 cases of COVID-19 and 95 deaths in the United States between Jan. 22 last year and April 12 this year, according to the CDC COVID data tracker.
Dr. Parchem and Ms. Carrig decided to get vaccinated because of their high risk of exposure to COVID-19 at work. After the second dose, Ms. Carrig reported chills but Bennett had no side effects from breastfeeding. Dr. Parchem, who delivered a healthy baby boy in February, reported no side effects other than a sore arm.
“There’s also a psychological benefit to returning to some sense of normalcy,” said Dr. Parchem. “My mother was finally able to visit us to see the new baby after we were all vaccinated. This was the first visit in more than a year.”