Prepregnancy body mass index and weight change on postpartum diabetes risk among gestational diabetes women

Objective To evaluate the effects of prepregnancy BMI and weight change from prepregnancy to postpartum on postpartum type 2 diabetes (T2D) risk among women with gestational diabetes (GDM). Methods A retrospective cohort study in 1,263 GDM women at 1-5 years after delivery was performed. Cox proportional hazards regression models were used to evaluate the association of prepregnancy BMI and weight change with T2D and prediabetes risks. Results The multivariable-adjusted hazard ratios based on different levels of prepregnancy BMI (<23, 23-24.9, 25-29.9, and ≥30 kg/m²) were 1.00, 1.77, 2.35, and 6.54 (P_trend<0.001) for incident T2D, and 1.00, 1.46, 1.87, and 1.79 (P_trend<0.001) for incident prediabetes, respectively. Compared with women with stable weight (±3 kg), those with weight gain ≥7 kg had an 86% and a 32% increased risk of diabetes and prediabetes, and those with weight loss ≥3 kg had a 45% decreased risk of prediabetes. The positive associations of prepregnancy BMI with incident diabetes and prediabetes risk were persistent in women with different levels of weight change (<3 kg and ≥3 kg). Conclusion Prepregnancy obesity and excessive weight gain from prepregnancy to postpartum increase postpartum diabetes and prediabetes risks among GDM women.