One year after gestational diabetes: metabolic changes and predictors of postpartum dysglycaemia

Background: Women with previous gestational diabetes mellitus (GDM) are at high risk of developing type 2 diabetes mellitus (T2DM). Although early postpartum screening is recommended, metabolic changes occurring during the first year remain poorly characterized, and Italian guidelines do not include assessment at this time point. Aim: To evaluate glycaemic and metabolic changes one year after delivery in women with previous GDM and identify clinical and lifestyle predictors of postpartum glucose impairment. Methods: A cohort of 134 women with prior GDM was assessed at 6–12 weeks (T0) and one year postpartum (T1). Anthropometric, biochemical, nutritional, lifestyle, and quality-of-life parameters were collected. Dietary habits were evaluated using a 3-day food diary and the PREDIMED questionnaire; physical activity was assessed using the International Physical Activity Questionnaire (IPAQ). Logistic regression models were used to identify predictors of altered OGTT at T1. Results: At baseline, 32.9% of women showed altered OGTT; this increased to 38.8% at one year, while T2DM prevalence rose from 2.2 to 5.2%. Insulin therapy during pregnancy was the only independent predictor of dysglycaemia at T1 (OR 3.5, 95% CI 1.28–9.50, p = 0.015). Women with altered OGTT reported lower SF-36 scores in the domains “role limitations due to physical health” (p = 0.016) and “health change” (p = 0.030). Breastfeeding was associated with more favourable glucose outcomes (p = 0.009). Conclusions: One-year follow-up after GDM reveals early metabolic and psychosocial differences not detectable in the early postpartum period. Insulin therapy during pregnancy strongly predicts glucose impairment, highlighting the need for extended postpartum surveillance and targeted lifestyle interventions.