Decay Rates of Maternal Tetanus, Diphtheria, and Pertussis Antibody Levels in Early and Moderate-to-Late Preterm and Term Infants at Birth and at Two Months

A post hoc analysis of maternally derived antibodies at birth and age 2 months following second trimester maternal Tdap vaccination between 20 and 24 weeks' gestational age (GA) showed a faster decay rate of Tdap-related immunoglobulin G in early preterms born before 32 weeks' GA compared with moderate-to-late preterms and full-terms. This is different from previous studies and merits further research.