 This study compared the incidence of gestational diabetes, pregnancy-related hypertension, pregnancy hemorrhage, preterm birth, and small for gestational age between pregnant women who received Tdap vaccination as part of the maternal immunization program in Brazil and unvaccinated women. The results showed no increased risk of pregnancy-related or neonatal adverse events following maternal vaccination with Tdap. However, these findings should be interpreted cautiously due to limitations inherent to retrospective observational studies.