LAUSR

Tetanus, diphtheria, and acellular pertussis (Tdap) vaccination and influenza vaccination are recommended during pregnancy primarily to prevent influenza and pertussis in mothers and their infants. This study examines associations between prenatal Tdap vaccination and influenza vaccination of mothers and hepatitis B vaccination of their infants. A retrospective cohort study was conducted using data from electronic medical records from 15,468 deliveries to 14,925 mothers occurring April 2, 2014-December 3, 2016 at a university hospital in Texas. Hepatitis B vaccine receipt in the first 3 days of life was dichotomized. Margins post-estimation commands in Stata SE 15.1 were used to obtain predicted probabilities and risk differences after estimating odds ratios in logistic regression with robust variance estimates. Adjusted models included maternal age, race/ethnicity, Medicaid use, year of delivery, parity, and gravidity. Infants of mothers who received prenatal influenza vaccination in the 2014-2015 and 2015-2016 influenza seasons were more likely than those of mothers who did not to receive a hepatitis B vaccine in their first 3 days of life (adjusted risk difference (RD) 2.8%, 95% confidence interval (CI) 1.5-4.1% and RD 2.2%, 95% CI 0.9-3.5%, respectively). Hepatitis B vaccination was also higher among infants of Tdap-eligible mothers who received prenatal Tdap vaccination during pregnancy compared to those of mothers who did not (adjusted RD 9.1%, 95% CI 7.6-10.5%). Overall, prenatal vaccination was significantly associated with uptake of infant hepatitis B vaccine.