evidence: Getting a COVID-19 vaccine during pregnancy significantly reduces the chance that a baby will be hospitalized for COVID-19, new data shows. The study from the CDC found that vaccines were 54% effective at protecting infants from COVID-19 hospitalization in the first 3 months of life, and 35% effective at protecting babies from ages 3 months through 5 months old. Infants can be vaccinated against COVID-19 starting at 6 months old. Infants who were hospitalized with COVID-19 whose mothers were unvaccinated were more likely to need help breathing, compared to infants whose mothers had been vaccinated. For the study, researchers analyzed data for 716 babies hospitalized between March 2022 and May 2023. Among the babies in the study, 377 were hospitalized with COVID-19. Mothers were considered vaccinated if they’d had at least two COVID vaccines, one of which was given during pregnancy. All other mothers of babies in the study were unvaccinated. Vaccinated mothers pass antibodies against COVID-19 through the placenta to the fetus. The authors noted that a limitation of the study was that prior infection of mothers was not analyzed, including among unvaccinated mothers. They also said it is possible that "infection-induced antibodies could provide some protection against infant COVID-19–related hospitalization." "Maternal vaccination during pregnancy provides some protection against COVID-19–related hospitalizations among infants, particularly those aged less than 3 months," the authors wrote. "Expectant mothers should remain current with COVID-19 vaccination to protect themselves and their infants from hospitalization and severe outcomes associated with COVID-19."