Narrowing Down the Best Tdap Window During Pregnancy

Cord blood levels of pertussis toxin antibody were highest when mothers received Tdap vaccine during gestational weeks 27 through 30.

To protect newborns against pertussis, maternal immunization with tetanus, diphtheria, and acellular pertussis (Tdap) vaccine is recommended during the third trimester. But is there an ideal vaccination timeframe within this period? Investigators in Houston conducted a prospective observational cohort study of term deliveries in 312 women who received third-trimester Tdap and 314 unimmunized women. Pertussis toxin antibody concentrations were measured in neonatal cord blood.

The geometric mean concentration of pertussis toxin antibodies was higher in cord blood of infants born to immunized women than in those born to unimmunized women (47 vs. 13 IU/mL; P<0.001). Antibody levels were highest in neonates whose mothers were immunized at 27 thro…

Reviewing Author

Anna Wald, MD, MPH

Disclosures

Consultant/Advisory BoardAicuris; Bayer; GSK; Innovative Molecules; Merck; MAPP Biopharmaceutical (Safety Monitoring Committee)

RoyaltiesUpToDate

Grant/Research SupportNIH/National Institute of Allergy and Infectious Diseases; GSK; Moderna; Assembly Biomedical; Aicuris

Editorial BoardsSexually Transmitted Diseases; Sexually Transmitted Infections; Journal of Infectious Diseases

Leadership PositionsID Division Chiefs Community of Practice (At-Large Member)