Barriers to influenza vaccination during pregnancy in France: A national population-based study.

Background: Despite French national recommendations since 2012 that all pregnant women be vaccinated against influenza, in 2021 this vaccine coverage is low - around 30 % - in France.

Objectives: To identify barriers to influenza vaccination during pregnancy by assessing how often women were offered this vaccination and how often they accepted it.

Study Design: We used data from the French national perinatal survey (ENP), which covered all births during one week in March 2021 (N = 12,614). Data came from medical files and face-to-face postpartum interviews. We excluded women who: refused to participate (n = 91), agreed only to complete the minimal questionnaire (n = 435), were not interviewed (N = 1130), or had medical records not mentioning influenza vaccination (N = 120). Factors associated with no offer of influenza vaccination during pregnancy and with refusal of offers that were made were assessed by univariate and multivariate analyses.

Results: Among the 10,838 women included, 40.7 % (95 % CI, 39.8-41.6) (n = 4411) reported that they had not been offered this vaccination. This group was younger, (adjusted prevalence ratio (PRa) for women below 25 years was 1.23 (95 % CI, 1.14-1.33)), multiparous more often (PRa 1.37 (95 % CI, 1.27-1.49)), born abroad more often (PRa 1.20, 95 %CI, 1.12-1.29 and less well educated (PRa 1.46 (95 %CI, 1.34-1.58). Among the 6427 women to whom influenza vaccination was offered during pregnancy, 3463 (53.9 %) were not vaccinated. This group was also younger, (PRa 1.23 (95 % CI, 1.14-1.33)), more often multiparous (PRa 1.18; 95 % CI, 1.07-1.30) and had a lower education level (PRa 1.70 (95 % CI, 1.56-1.85)).

Conclusion: The low influenza vaccine coverage in France seems mainly related to the failure to offer the vaccine, in particular to those young and less educated. Our study identifies key points of leverage to improve vaccine coverage and reduce the persisting burden of this severe infection.