Insufficient physical activity (PA) during pregnancy is a global public health concern. The aims of this study were: i) to determine retrospectively PA and sedentary time in women in the second trimester of pregnancy, and ii) to identify factors that influence adherence to the French National College of Midwives guidelines on PA (≥150 minutes of moderate to high-intensity PA per week).

This cross-sectional, single-centre study, conducted at the University Hospital of Rennes, included 195 pregnant women. PA levels and sedentary time before and during the second trimester of pregnancy were determined using an anonymous self-report questionnaire. The self-reported PA levels were compared to the guidelines on PA. Bivariate analyses and Poisson generalized linear regression models were used to identify factors associated with non-compliance to such guidelines.

Only 30.7 % of pregnant women reported the recommended PA levels in the second trimester of pregnancy. Sedentary time and adherence to the PA guidelines were not associated. Fatigue was the most frequently cited reason for insufficient PA (71.6 %). Preconception PA level was the strongest predictor of adherence. Body mass index >25 kg/m², <2 years of higher education, limited access to transportation and sports facilities, and living in a town with <2.000 inhabitants also were associated with lower PA levels.

Adherence to the PA recommendations is low among French pregnant women. Public health initiatives should emphasize PA importance before pregnancy and provide tailored support throughout gestation. Future studies should explore the interplay between PA, sedentary time and pregnancy outcomes.