Association between pregnancy cumulative glycemic exposure and postpartum glucose metabolism outcomes at 4-7 years: a cohort study.

OBJECTIVE: This study aimed to investigate the association between cumulative glycemic exposure (CGE) during pregnancy and glycemic metabolism abnormality (GMA) at 4-7 years postpartum and to compare its predictive value with that of a single fasting blood glucose (FBG) measurement. METHODS: In this retrospective-prospective cohort study, 120 pregnant women were included from an existing cohort. CGE was calculated using the trapezoidal rule, and subjects were categorized into tertiles. A logistic regression analysis evaluated the association between CGE and GMA, and restricted cubic splines were used to evaluate dose-response relationships. The interaction between CGE and pre-pregnancy body mass index (BMI) was examined. Predictive performance was compared using receiver operating characteristic (ROC) curves. RESULTS: Higher CGE was associated with an increased incidence of GMA [tertile 1 (T1): 10.0%, T2: 35.0%, T3: 65.0%]. Each 1-unit increment in CGE independently increased GMA risk (odds ratio = 1.040, 95% confidence interval: 1.01-1.07, p = 0.028). Compared with T1, the risk of GMA was 3.85-fold higher in T2 and 15.82-fold higher in T3 (p < 0.05). FBG at 8 and 24 weeks, but not 34 weeks, significantly predicted GMA. A non-linear dose-response between CGE and GMA was observed (inflection point: 192.67 mmol/L·week). An additive interaction between CGE and pre-pregnancy BMI was observed. The combined model (CGE + pre-pregnancy BMI) provided the best prediction [area under the curve (AUC): 0.843, sensitivity: 85.5%, specificity: 79.1%]. CONCLUSION: CGE during pregnancy is an independent predictor of postpartum GMA. In clinical practice, adding pre-pregnancy BMI improves risk stratification, supporting the early identification of high-risk women. CLINICAL TRIAL REGISTRATION: Identifier ChiCTR2300067592.