Could tighter glucose control during pregnancy help lower obesity risk in children exposed to gestational diabetes mellitus (GDM)? A population-based prospective cohort study published in Diabetes Care found that early and sustained glycemic management after GDM diagnosis was associated with childhood obesity risk comparable to that of offspring unexposed to GDM.

The study included 206,464 pregnant individuals who delivered at Kaiser Permanente Northern California between 2011 and 2017, with offspring body mass index (BMI) measured from ages 2 to 10 years through 2022. Among these pregnancies, 14,870 (7.2%) involved GDM. Four maternal glycemic management trajectories were identified from diagnosis to delivery: stably optimal (T1), rapidly improving to optimal (T2), slowly improving to near optimal (T3), and slowly improving to suboptimal (T4). Optimal control was defined as at least 80% of glucose values meeting American Diabetes Association targets.

A dose-response pattern was observed across trajectories. By age 10, offspring in T1 had BMI and obesity risk similar to children unexposed to GDM (risk ratio [RR], 1.07; 95% confidence interval [CI], 0.91-1.26). In contrast, offspring in T2, T3, and T4 showed progressively higher obesity risk, with RRs of 1.37 (95% CI, 1.18-1.59), 1.53 (95% CI, 1.29-1.81), and 1.62 (95% CI, 1.33-1.98), respectively. BMI also increased stepwise across these groups.

Associations were reduced but remained present after adjustment for prepregnancy BMI. These findings suggest that prompt and sustained glycemic control after GDM diagnosis may offer an early opportunity to reduce long-term obesity risk in offspring.