Written by Dr. John Yoon
A recent study published in the American Journal of Obstetrics and Gynecology provided scientific evidence that the COVID-19 mRNA vaccines – both Pfizer and Moderna – are effective in pregnant and breastfeeding women.
Why was this study conducted?
– Scientific evidence was lacking regarding vaccine efficacy in a pregnant and breastfeeeding population and whether vaccination would offer any passive immunity to the newborn baby.
– As of March 1, 2021, there have been more than 73,600 infections and 80 maternal deaths in pregnant women in the United States.
– The absolute risk of acquiring COVID-19 in pregnancy is low, however pregnancy remains a risk factor for severe disease, with an increased risk of hospital admission, ICU stay, and death.
– In lieu of these findings pregnant women were not included in the initial vaccine trials.
– Specifically this study focused on the two novel mRNA vaccines (Pfizer and Moderna).
What are the study findings?
– Pregnant and breastfeeding women displayed a similar vaccine induced immune response when compared to non-pregnant controls.
– Pregnant women were noted to have higher antibody titers following COVID-19 vaccination when compared to natural COVID-19 infection during pregnancy.
– Vaccine induced antibodies were present in umbilical cord blood and breast milk after maternal vaccination.
Why does this matter?
– Previous recommendations were made on assumptions that pregnant women would generate similar responses to non-pregnant people.
– First study to demonstrate maternal antibody formation in pregnant women after administration of the COVID-19 mRNA vaccine.
– Demonstrates in pregnant women who have had been infected naturally with COVID-19 would benefit from vaccination
– Suggests that vaccination of pregnant and breastfeeding women confers immunity both to pregnant women and their newborn baby.
What doesn’t this study show?
– This study did not address vaccine safety and any adverse pregnancy outcomes.
– As of March 22nd, the CDC v-safe program is tracking over 60K pregnant women who have self-reported to have been vaccinated while pregnant- There continue to be no concerning pregnancy outcomes, pregnancy complications or neonatal outcomes over the general population.
– This study does not indicate which trimester is the ideal time for optimal transfer of antibodies