A new study examining coronavirus vaccine response in pregnant and nursing women found that antibodies from mothers were present in their umbilical cord blood and breast milk, suggesting that inoculated women who are pregnant or breastfeeding may pass immunity on to babies.
The results suggested that “the baby does have protection; we just don’t know how long it will last,” Andrea Edlow, a co-author of the study, told NBC News.
The study also found that pregnant and breastfeeding women who receive the vaccine developed a “robust humoral immunity” to COVID-19, one that is comparable to women who are not pregnant or nursing.
However, the study, published by the American Journal of Obstetrics & Gynecology was not meant to determine if the vaccine is safe for pregnant and nursing women to receive, Edlow noted to NBC News.
Edlow said its findings are essential for OB-GYNs and other doctors because pregnant and nursing women were largely left out of vaccine trials, which left medical professionals with “a complete lack of data.”
The Centers for Disease Control and Prevention, however, noted that experts believe vaccines “are unlikely to pose a specific risk for people who are pregnant,” based on how they work in the body. They did note though that there is limited data on the topic.
The study, which took place at two academic medical centers, included 131 reproductive-age women, including 84 who were pregnant, 31 who were lactating, and 16 who were not pregnant for a control group. The participants were administered two doses of either the Pfizer or Moderna COVID-19 vaccines.
On Feb. 18, Pfizer and BioNTech announced a new trial to test the safety and efficacy of the coronavirus vaccine in pregnant women.