Gestational Diabetes Mellitus, Glycemic Management Trajectories, and Offspring Growth Patterns and Obesity Risk

OBJECTIVE: Children exposed to gestational diabetes mellitus (GDM) face an increased risk of obesity. We examined whether offspring obesity risk varied by maternal glycemic management trajectories during pregnancy compared with offspring unexposed to GDM. RESEARCH DESIGN AND METHODS: This population-based prospective cohort included individuals who delivered at Kaiser Permanente Northern California (2011-2017) and their offspring with BMI measured at ages 2-10 years through 2022. Glycemic management trajectories (optimal ≥80% of glucose values meeting American Diabetes Association targets) were identified from GDM diagnosis to delivery. Associations with offspring BMI and obesity risk were estimated using adjusted generalized estimating equations. RESULTS: Among 206,464 pregnant individuals, 14,870 (7.2%) had GDM, among whom four glycemic management trajectories were identified: stably optimal (T1), rapidly improving to optimal (T2), slowly improving to near optimal (T3), and slowly improving to suboptimal (T4). Associations showed a dose-response pattern across T1-T4. By age 10, offspring in T1 had BMI (β = 0.27 [95% CI -0.13, 0.66]) and obesity risk (risk ratios 1.07 [0.91, 1.26]) similar to those of offspring unexposed to GDM. In contrast, offspring in T2, T3, and T4 had progressively higher BMI (1.00 [0.55, 1.46], 1.22 [0.67, 1.76], and 2.15 [1.48, 2.49]) and obesity risk (1.37 [1.18, 1.59], 1.53 [1.29, 1.81], and 1.62 [1.33, 1.98]). Associations were attenuated but persisted after adjustment for prepregnancy BMI. CONCLUSIONS: Early and sustained glycemic management after GDM diagnosis was associated with lower childhood obesity risk comparable to that in offspring unexposed to GDM. These findings suggest an opportunity for prenatal risk stratification and prevention for children at higher obesity risk.