Efficacy, Immunogenicity, and Safety of Pertussis Vaccine During Pregnancy: A Meta-Analysis.

BACKGROUND

A growing number of countries implement prenatal pertussis vaccination policies to safeguard unvaccinated infants. This meta-analysis aimed to evaluate the efficacy, immunogenicity, and safety of antenatal Tdap vaccination in pregnant individuals.

METHODS

We systematically searched PubMed, Embase, and Web of Science from their inception to 16 February 2025, rigorously screening studies and including seven randomized controlled trials and 10 case-control studies published between 2014 and 2024. For the test-negative design meta-analysis, odds ratios with 95% confidence intervals served as effect estimates, and vaccine efficacy was calculated accordingly. Standardized mean differences were used to assess geometric mean concentrations, while relative risks evaluated safety.

RESULTS

Maternal vaccination during pregnancy demonstrated 85% vaccine effectiveness (95% CI: 78-89%) in protecting infants under 3 months old. Pooled standardized mean differences for cord blood IgG antibodies against pertussis toxin, pertactin, and filamentous hemagglutinin were 1.57 (95% CI: 1.25-1.89), 2.15 (95% CI: 1.82-2.48), and 2.25 (95% CI: 1.81-2.68), respectively, indicating higher antibody levels in infants of vaccinated women before their first immunization. Safety analysis showed no significant association between Tdap vaccination during pregnancy and serious adverse events in infants (RR = 0.76, 95% CI: 0.46-1.24) and pregnant women (RR = 1.22, 95% CI: 0.83-1.81).

CONCLUSION

Our findings support the implementation of pertussis vaccination during pregnancy.