Glucose Levels During Gestational Diabetes Pregnancy and the Risk of Developing Postpartum Diabetes or Prediabetes
Abstract Background: Blood glucose levels during pregnancy may reflect the severity of insulin secretory defects and/or insulin resistance during gestational diabetes mellitus (GDM) pregnancy. We hypothesized that suboptimal glycemic control in women with GDM could increase the risk of postpartum type 2 diabetes mellitus (DM) or prediabetes. Our objective was to evaluate the impact of plasma glucose levels throughout GDM pregnancy on the risk of postpartum type 2 DM or prediabetes. Methods: The medical records of 706 women with GDM who underwent a postpartum 75-g oral glucose tolerance test at our institution between January 2011 and December 2018 were reviewed. These women were classified into 2 groups according to glycemic control during pregnancy: ≤ 1 occasion of either fasting glucose ≥ 95 mg/dL or 2-h postprandial glucose ≥ 120 mg/dL was defined as optimal glycemic control or else was classified as suboptimal glycemic control. Rates of postpartum type 2 DM and prediabetes were compared between women with optimal (n = 505) and suboptimal (n = 201) glycemic control. Results: The rates of postpartum type 2 DM and prediabetes were significantly higher in the suboptimal glycemic control group than in the optimal glycemic control group: 22.4% vs. 3.0%, P < 0.001 for DM and 45.3% vs. 23.6%, P < 0.001 for prediabetes. In a multivariate analysis, suboptimal glucose control during pregnancy was an independent risk factor for developing either postpartum type 2 DM or prediabetes. The adjusted odds ratios were 18.9 (95% confidence interval, 7.0–50.7) for DM and 4.1 (95% confidence interval, 2.6–6.4) for prediabetes. Conclusion: Our findings suggest that blood glucose levels during GDM pregnancy have an impact on the risk of postpartum type 2 DM and prediabetes.