Factors impacting the recent doubling of French hyperglycaemia prevalence in pregnancy

To assessed hyperglycaemia in pregnancy (HIP) prevalence trends over the past decade, accounting for risk factors and screening practices (France introduced early risk-based HIP screening in 2010).

We analysed national delivery data from the French National Health Data System (SNDS) (2012-2022), excluding women with pre-existing diabetes (n=8,172,911). Poisson regressions with generalized estimating equations estimated prevalence ratios (PR) for HIP risk factors. Counterfactual scenarios quantified contributions of maternal age, early screening, and pre-pregnancy overweight to HIP increase.

HIP prevalence increased from 7.5% in 2012 to 15.7% in 2022, with early HIP tripling. Prevalence rose in 2020-2021 during the Covid-19 pandemic. After adjustment for maternal age, parity, socioeconomic status, season of pregnancy onset, place of delivery, regional prevalence of pre-pregnancy overweight, and early screening, the aPR were 1.30 [1.11-1.51] in 2021 and 1.15 [0.97-1.36] in 2022 vs. 2012 (unadjusted: 2.24 [2.22-2.26] and 2.08 [2.06-2.10]), suggesting that these factors account for a large proportion of the observed increase. While the observed increase in HIP prevalence was 8.2 percentage points from 2012 to 2022, counterfactual scenarios estimated increases of 6.5 [5.9-7.3] for constant maternal age, 6.2 [5.1-7.7] for constant early screening (13.7%), and 4.3 [2.4-5.9] for constant regional pre-pregnancy overweight (11.8%) at 2012 levels.

Rising maternal age, increased early HIP screening, and higher regional pre-pregnancy overweight prevalence mostly contributed to HIP prevalence increase. Public health strategies should prioritize modifiable risk factors-particularly pre-pregnancy overweight-and evaluate the effectiveness of early screening practices.