Adherence and Concordance of Influenza and Pertussis Vaccination Coverage in Pregnant Women in Spain

Background: Pregnant women should receive two vaccines during pregnancy due to maternal-foetal complications and risks as well as the influenza and pertussis vaccinations. The goal was to evaluate vaccination coverage against influenza and pertussis in pregnant women, following midwife professional advice during the pregnancy follow-up; Methods: Prospective cohort study of 1017 pregnancies during the vaccination campaign in 2015-2016. To estimate the degree of consistency between the coverage declared by mothers and that registered in the Nominal Vaccination Registry (NVR), we used the Cohen's kappa index (k); Results: 95.4% were registered in the NVR. Vaccination coverage recorded against influenza was 64.2% (95% CI: 61.2-67.2), and 89.8% (95% CI: 87.9-91.7) against pertussis. The coverage of the pregnant women interviewed was 61.7% (95% CI: 58.1-67.3)) for influenza and 92.3% (95% CI: 91.4-95.3) for pertussis. Subsequent interviews of 67.2% of the women produced a kappa agreement index between the data obtained from interviews and those recorded in the NVR of 0.974 (IC95%: 98.0-99.6) for influenza, and 0.921 (IC95%: 98.1-99.7) for pertussis. The women identified midwives as the main source of vaccination information and advice 88.4% (IC95%: 85.8-90.9); Conclusions: The NVR is an effective platform for estimating immunisation coverage in pregnant women. The degree of agreement between declared vaccinations and registered vaccinations was high for both vaccines.