Factors associated with Tdap vaccination receipt during pregnancy: a cross-sectional study

Pertussis morbidity and mortality disproportionately affect infants younger than 1 year, who constitute 70% of deaths from pertussis. In 2017, 43% of infants younger than 6 months diagnosed with pertussis were hospitalized. In 2012, the Advisory Committee on Immunization Practices recommended that all pregnant women should receive Tdap (tetanus-diphtheria-acellular pertussis) vaccine between 27- and 36-weeks gestation in an effort to reduce infant pertussis morbidity and mortality. However, Tdap vaccination rates among pregnant women remain far from robust. The aim of this study was to assess factors associated with maternal Tdap uptake to help providers identify best practices that can improve Tdap receipt and identify women at risk for not receiving this important vaccine.

A retrospective cross-sectional study.

A review of prenatal and delivery records was performed on all maternal-infant dyads with infants older than 36 weeks gestation admitted to the term nursery at Albany Medical Center from January 1, 2016 to April 16, 2016. A chi-squared analysis using STATA®, version 14.1, was performed to determine if any variables were associated with Tdap uptake, with statistical significance defined as P < 0.05. Multivariate analysis was performed to identify the variables which had the greatest effect on Tdap receipt.

Tdap vaccine was received by 65.8% of pregnant women (n = 400) in the study; median gestational age of receipt was 30 weeks. Maternal influenza vaccine receipt, infant hepatitis B vaccine receipt, provider recommendation of Tdap vaccination, and on-site availability of Tdap vaccine were all positively associated with maternal Tdap receipt during pregnancy.

Receipt of Tdap by pregnant women was highest in those who had received a provider recommendation about its benefits and who also received influenza vaccine during pregnancy. Because women who received the influenza vaccine themselves and also consented to have their infants receive the hepatitis B vaccine had significantly higher uptake rates, encouraging vaccines usage and combating vaccine hesitancy in general can improve Tdap uptake rates. A small, but statistically significant association with receipt of assisted reproductive technologies was also seen, meriting future research.