Less than one-third of pregnant people are fully vaccinated, and false information about the impact of coronavirus vaccination may be the reason the rate is so low. There is robust — and growing — evidence that the vaccine is safe for pregnant people and their unborn babies but, like many aspects of the pandemic, rumors are proliferating faster than experts can fight them.
“There has been a lot of misinformation floating around out there about vaccination in pregnancy and spurious claims that it can affect future fertility. There is no factual basis to these claims, yet unfortunately it has made many hesitant to receive vaccines,” said Carleigh Krubiner, a nonresident fellow at the Center for Global Development and associate faculty member at the Johns Hopkins Berman Institute of Bioethics. “This is especially tragic as more and more stories emerge of young women and pregnant people who forewent vaccination out of fears only to fall seriously ill or die from severe covid-19.”
Jeanne Sheffield, director of the division of maternal-fetal Medicine and a professor in the Johns Hopkins Medicine Department of Gynecology and Obstetrics, said she’s fielding two to three queries daily from women concerned about how the vaccines might impact pregnancy and fertility.
“I tell them I understand completely, because the second you become pregnant, you’re suddenly a mother and you’re very protective of this unborn child,” said Sheffield. “I start out by telling them how covid can manifest in pregnancy, how bad it can be in pregnancy, how incredibly sick pregnant women can get and some of the consequences to the baby if the mother gets that sick.”
So far, well over 120,000 pregnant women in the United States have contracted covid-19, and 159 of them have died.
Sheffield also tells her patients that hundreds of thousands of pregnant women have now been vaccinated without any increase in complications.
Despite this, vaccinations among pregnant people lag far behind the general adult population, almost 55 percent of whom are now fully vaccinated.
We’ve compiled answers to some of the most commonly asked questions about pregnancy and coronavirus vaccines in consultation with guidance from the Centers for Disease Control and Prevention and interviews with experts specializing in fetal and maternal health, infectious diseases and immunizations in pregnancy.
Given the safety of the vaccine and the potentially lethal effects of covid-19 on pregnant people, the CDC recommends that everyone who is pregnant, breastfeeding or trying to get pregnant get a coronavirus vaccination. The major medical organizations specializing in pregnancy and childbirth, the American College of Obstetrics and Gynecologists and the Society for Maternal-Fetal Medicine, agree.
“CDC encourages all pregnant people or people who are thinking about becoming pregnant and those breastfeeding to get vaccinated to protect themselves from COVID-19,” said CDC Director Rochelle Walensky in an August statement. “The vaccines are safe and effective, and it has never been more urgent to increase vaccinations as we face the highly transmissible Delta variant and see severe outcomes from COVID-19 among unvaccinated pregnant people.”
The CDC came to this conclusion after conducting a study of almost 2,500 pregnant women who received a coronavirus vaccine and finding no increased risk of miscarriage. The CDC and the Food and Drug Administration also have three safety monitoring systems in place for health-care professionals, medical organizations, vaccine manufacturers and the general public to report and monitor concerns, irregularities or side effects of the vaccination in pregnant people. These monitoring systems have not raised any safety concerns.
In a study of women with covid-19, about one-third of pregnant women were hospitalized as compared to less than 6 percent of nonpregnant women. Pregnant women were significantly more likely to end up in an ICU and on a ventilator.
This elevated risk is why experts say it is so critical for pregnant people to get vaccinated, which is the best way to prevent severe illness from the disease.
“These vaccines do not pose a threat to those who want to have healthy babies in the near or long-term, but the ongoing threat of covid-19 among the unvaccinated certainly can jeopardize the health and well-being among those who plan to have kids someday,” said Krubiner.
Pregnant people are typically excluded from vaccine trials, and virtually all clinical trials. Coronavirus vaccine trials were no different.
“Unfortunately, there is a long-standing history of excluding pregnant people from biomedical research trials, even when the prospect of benefits clearly outweighs potential risks,” said Krubiner, who has helped develop guidelines for safely and ethically including pregnant people in clinical trials.
Although pregnant women were not deliberately included, 23 women participants became pregnant during the Pfizer vaccine trials, offering the first data on the safety of the vaccine during pregnancy. The only participant who experienced a pregnancy loss had received a placebo, rather than the vaccine.
There is no evidence that coronavirus vaccines impact fertility.
Misinformation on this topic has spread online, including numerous false reports that conflated a spike protein on the coronavirus with the spike protein needed for placenta growth and pregnancy called syncytin-1. The misinformation claimed that the vaccine will cause women’s bodies to target syncytin-1, which is untrue.
“The best vaccine is any vaccine that you can get,” said Brenna L. Hughes, associate professor of obstetrics and gynecology at Duke University School of Medicine.
The majority of the data released so far has been on mRNA vaccines, so Moderna and Pfizer have the most information available to support safety and efficacy in pregnancy. However, Hughes says this is largely because they were approved earliest and that she would also encourage people to take the Johnson & Johnson single-shot coronavirus vaccine if that was what was available.
Not only have studies found that there is no increased chance of miscarriage after receiving the vaccine, getting vaccinated during pregnancy may offer a major benefit to the future baby: antibodies to protect it against a coronavirus infection. In a small but promising new study, every infant whose mother received the Pfizer–BioNTech or Moderna coronavirus vaccine during pregnancy was born with protective antibodies passed along in utero. Women who are breastfeeding when they get vaccinated can also pass these antibodies through breast milk, according to a study published in Pediatrics this month.
Moreover, ongoing research shows that the effects of contracting a severe case of covid-19 in pregnancy can also contribute to preterm labor, or worse. David A. Schwartz, a specialist in perinatal pathology and global maternal health in Atlanta, is part of ongoing research that has found that coronavirus infections in a small percentage of pregnant women can damage the placenta, which in severe cases may diminish the fetus’s oxygen supply and cause fetal death and stillbirth.
“This is clearly not only a maternal life-saving vaccine but I think a fetal life-saving vaccine,” said Schwartz. “Our rigorous scientific and epidemiological studies are showing that this vaccine is as safe as can be.”