Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2023 Feb;12(2):411-423.
doi: 10.1007/s40121-022-00731-8. Epub 2022 Dec 15.

Investigating Tetanus, Diphtheria, Acellular Pertussis Vaccination During Pregnancy and Risk of Congenital Anomalies

Affiliations

Investigating Tetanus, Diphtheria, Acellular Pertussis Vaccination During Pregnancy and Risk of Congenital Anomalies

Ana Florea et al. Infect Dis Ther. 2023 Feb.

Abstract

Introduction: This observational retrospective matched cohort study evaluated the safety of a prenatal tetanus, diphtheria, acellular pertussis (Tdap) vaccination, Boostrix. We previously reported on the risk of maternal and neonatal outcomes; here we report on the risk of congenital anomalies in infants at birth through 6 months of age.

Methods: The study included pregnant Kaiser Permanente Southern California members. Women who received the Tdap vaccine on or after the 27th week of pregnancy between January 2018 and January 2019 were matched to women who were pregnant between January 2012 and December 2014 and were not vaccinated with Tdap during pregnancy. Unadjusted and adjusted relative risks (aRRs) with 95% confidence intervals were estimated by Poisson regression. Quantitative secular trend analyses, from 2011 to 2017, were conducted on congenital anomalies with a statistically significant aRR > 1.

Results: The analysis consisted of 16,350 and 16,088 live-born infants in the Tdap-exposed and unexposed cohorts, respectively. Of the 14 congenital anomaly body systems evaluated, 8 (eye, ear/face/neck, respiratory, upper gastrointestinal, genital, renal, musculoskeletal, integument) had statistically significant elevated aRRs, with point estimates ranging from 1.17 to 2.02. The observed elevated aRRs were consistent with their respective secular increases over time.

Conclusion: Cautious interpretation of these findings is warranted as these increases may have resulted from improved identification and diagnosis. Furthermore, the biological plausibility of an association between maternal vaccine exposure in the third trimester of pregnancy and birth defects is low. The overall study findings support the safety of maternal immunization with Boostrix during the third trimester of pregnancy.

Trial registration: ClinicalTrials.gov identifier, NCT03463577.

Keywords: Congenital anomalies; Maternal immunization; Observational study; Tdap; Vaccine safety.

PubMed Disclaimer

References

    1. World Health Organization. Congenital anomalies. https://www.who.int/news-room/fact-sheets/detail/congenital-anomalies. Accessed 9 Sept 2021.
    1. Centers for Disease Control and Prevention. Data and statistics on birth defects. https://www.cdc.gov/ncbddd/birthdefects/data.html. Accessed 9 Sept 2021.
    1. Centers for Disease Control and Prevention. Birth defects—surveillance of congenital anomalies. https://www.cdc.gov/ncbddd/birthdefects/surveillancemanual/chapters/chap.... Accessed 9 Sept 2021.
    1. DeSilva M, Munoz FM, Mcmillan M, et al. Congenital anomalies: case definition and guidelines for data collection, analysis, and presentation of immunization safety data. Vaccine. 2016;34(49):6015–6026. doi: 10.1016/j.vaccine.2016.03.047. - DOI - PMC - PubMed
    1. Shiota K. Variability in human embryonic development and its implications for the susceptibility to environmental teratogenesis. Birth Defects Res A. 2009;85(8):661–666. doi: 10.1002/bdra.20596. - DOI - PubMed

Associated data

LinkOut - more resources