(253) COVID-19 vaccination rate among pregnant women in France: a nationwide study

Background: Pregnant women are at an elevated risk for severe COVID-19, but nationwide rates of vaccination and its timing during pregnancy are not well documented.

Objectives: To assess COVID-19 vaccination rates among pregnant women in France, compare them to those of the general population, and analyze factors associated with vaccination status and timing.

Methods: We conducted a nationwide study using the French National Health Data System (SNDS) and EPI-MERES register, including all pregnant women who delivered after 22 weeks of amenorrhea, between April 1, 2021, and December 31, 2022. For comparison, the vaccination rate in the general female population residing in France was standardized based on age, ecological and individual social deprivation indicators. Socio-demographic factors, pregnancy monitoring indicators, pre-existing comorbidities, were analyzed according to vaccination status and trimester of pregnancy at vaccination. Differences were compared using multivariable logistic regression models.

Results: Among 1 209 581 pregnant women, 53% had received at least one vaccine dose by the end of their pregnancy. Of those, 7%, 19%, and 12% received it respectively, during their 1st, 2nd and 3rd trimester of pregnancy, while 61% received it before conception. Vaccination rates initially lagged behind those of the general population but converged by June 2022, with a six-month lag. Younger and more socially deprived women were less highly vaccinated. Unvaccinated women were more likely in their third pregnancy (adjusted OR [IC95%]: 1.17 [1.16 – 1.18]), underwent less routine ultrasound scans (aOR, 0.71 [0;70 – 0.72] for 1st-trimester scan), took less folic acid (0.74 [0.73 – 0.74]). Women with comorbidities, such as obesity, diabetes, hypertension, antidepressant use, or chronic respiratory disease, were more often vaccinated (aORs ranged from 0.70 to 0.90). Pregnant women vaccinated during their 1st trimester or 3rd trimester were younger and more socially deprived than those vaccinated during their 2nd trimester or before conception, possibly because the health pass was implemented at the same time 1st-trimester vaccination started to be recommended.

Conclusions: Pregnant women in France were less highly vaccinated than the general population during crucial pandemic periods but eventually reached similar vaccination rates. Socioeconomic status and the level of prenatal care were strongly associated with low vaccine uptake. The study underscores the need for targeted public health strategies to improve vaccine uptake in pregnant women.