Context: Gestational diabetes mellitus (GDM) is a recognized risk for abnormal glucose tolerance (AGT) long-term. Aims: The aim of this study is to determine the prevalence of postpartum diabetes and AGT and predictive factors among Sri Lankan women with GDM. Settings and Design: The follow-up study was conducted in Gampaha District, Sri Lanka. Materials and Methods: Pregnant women with GDM were identified by a community-based longitudinal study (n = 1200) by WHO 1999 criteria and followed up till 1 year postpartum. Study instruments were interviewer-administered questionnaire, anthropometric measurements, and fasting 75 gOGTT. Statistical Analysis Used: χ² tests with P-values and odds ratios (ORs) with 95% confidence interval (CI) were used to assess the statistical significance and strength of the associations. Predictive factors of postpartum AGT were identified by the multivariate analysis. Results: Of those identified with GDM (194), 169 participated in postpartum follow-up at 2 months (87.1%). Of the 169, 59 participated at 1 year. At 2 months, 17/169 (10.1%) had diabetes and 55/169 (32.5%) had AGT (diabetes=17, impaired glucose tolerance= 36, impaired fasting glucose=2). At 1 year, 11/59 (18.6%) had diabetes and 28/59 (47.5%) had AGT. Predictive factors of postpartum AGT at 2 months were 2-h postprandial blood sugar (2-h PPBS) before 12 weeks ≥97.5 mg/dL (adjusted OR (aOR)=2.8; 95% CI=1.3–6.0), GDM diagnosis before 16 weeks (aOR=7.7; 95% CI=1.5–39.7), and 1-h oral glucose tolerance test (OGTT) ≥179 mg/dL (aOR=3.1; 95% CI=1.5–6.4). Predictive factors of postpartum AGT at 1 year were 2-h PPBS before 12 weeks ≥97.5 mg/dL (aOR=8.4; 95% CI=2.3–30.3) and physical activity (aOR= 0.2; 95% CI=0.1–0.8). Conclusion: Postpartum AGT following GDM is high among Sri Lankan women. Long-term follow-up is recommended.

Keywords: 75 gOGTT, GDM, gestational diabetes mellitus, postpartum abnormal glucose tolerance, predictive factors