Current guidelines recommend that pregnant people receive a vaccine against respiratory syncytial virus (RSV)-;which typically causes mild, cold-like symptoms in most adults but can be deadly for infants-;during weeks 32–36 of pregnancy. New research led by investigators at Mass General Brigham suggests that vaccination earlier in that timeframe, closer to 32 weeks, could provide the best protection for newborns against RSV. The findings are published in the American Journal of Obstetrics & Gynecology .
Receiving the RSV vaccine in pregnancy is an important way mothers can protect their newborns and infants from RSV, the leading cause of hospitalization in U.S. infants.
However, it wasn't clear whether it was equivalent to vaccinate at any time within the approved window, or whether specific weeks were most optimal. Because the RSV vaccine was ultimately approved for administration during a narrower gestational age window than was originally studied in the large clinical trial, more information was needed about how maternal antibodies travel across the placenta week over week across the approved window." Andrea Edlow, MD MSc, senior author, maternal-fetal medicine specialist in the Department of Obstetrics and Gynecology at Massachusetts General Hospital, a founding member of the Mass General Brigham healthcare system Edlow and her team's prior work evaluating prenatal administration of the COVID-19 mRNA vaccines demonstrated that timing of maternal vaccination was associat.