Maternal immunization with tetanus-diphtheria-pertussis vaccine: effect on maternal and neonatal serum antibody levels.

OBJECTIVE: We sought to determine whether tetanus-diphtheria-pertussis vaccination (Tdap) in pregnancy provides newborns antibodies against pertussis when compared to mothers who did not receive Tdap. STUDY DESIGN: Paired maternal and umbilical cord blood samples were collected at the time of delivery and the serum stored at -86°C. For each paired sample of maternal and cord blood, the medical chart and vaccine history was reviewed to determine whether Tdap was received or not. RESULTS: Newborns born from mothers who received Tdap during pregnancy had significantly higher concentrations of diphtheria antitoxin (P < .001), tetanus antitoxin (P = .004), and antibodies to pertussis toxin (P < .001), filamentous hemagglutinin (P = .002), pertactin (P < .001), and fimbriae 2/3 (P < .001) when compared to newborns from mothers who did not receive Tdap. There was a significant increase in the odds that newborns from mothers who received Tdap during pregnancy have antibodies that may provide protection against diphtheria (P = .0141), pertussis toxin (P < .0001), and fimbriae 2/3 (P = .0146). CONCLUSION: Administering Tdap during pregnancy increases antibody titers against diphtheria and pertussis antigens. Maternal Tdap may prevent neonatal pertussis infection.