Trends in Tdap vaccination among privately insured pregnant women in the United States, 2009–2016

AbstractBackgroundInfants younger than 6 months are at increased risk of complications and mortality from pertussis infection. In October 2012, the Advisory Committee on Immunization Practices revised its recommendation to include a Tdap dose during each pregnancy, ideally between 27 and 36 weeks gestation. ObjectiveAssess trends in Tdap vaccination coverage among privately insured pregnant women from 2009 to 2016 including timing of Tdap vaccination (before, during, or after pregnancy), trimester of vaccination for women vaccinated during pregnancy, and missed vaccination opportunities for unvaccinated women. Identify factors associated with vaccination during the optimal period of 27–36 weeks gestation. Study designRetrospective analysis of privately insured women 15–49 years who delivered live births during 2009–2016 conducted using 2009–2016 MarketScan data. Tdap vaccination coverage and the timing of Tdap vaccine administration were assessed for women continuously enrolled from 6 months before pregnancy to 1 month after delivery. Multivariable logistic regression was performed to identify factors independently associated with receipt of Tdap vaccine at 27–36 weeks gestation. ResultsTdap vaccination coverage during pregnancy increased from 0.4% in 2009 to 6.2% in 2012 and to 53.2% in 2016. The proportion of vaccinated women receiving Tdap at 27–36 weeks gestation increased from