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 and Gynecology.