Maternal and child outcomes reported by breastfeeding women following mRNA COVID-19 vaccination

Abstract

INTRODUCTION Clinical trials for both the Pfizer-BioNTech BNT162b2 and Moderna mRNA-1273 COVID-19 vaccines demonstrated their ability to prevent infection and severe disease, leading to emergency use authorization by the U.S. Food and Drug Administration. The American College of Obstetrics and Gynecology and The Society for Maternal Fetal Medicine have recommended that these novel mRNA vaccines be made available for lactating women. However, initial trials excluded breastfeeding women, leading to questions about their safety.3 One study of 31 breastfeeding women who received one of the mRNA vaccines found that >60% reported side effects.4 We sought to evaluate a larger sample of vaccinated breastfeeding women and their children.