Risk factors associated with postpartum impaired glucose regulation in women with previous gestational diabetes

Aims: For women with previous gestational diabetes (GDM), international guidelines recommend 75 g oral glucose tolerance test (OGTT) at 4–12 weeks after delivery to assess glucose tolerance, considering their increased risk of type 2 diabetes. We evaluated prevalence of postpartum impaired glucose regulation (IGR) and identified associated risk factors. Methods: We retrospectively collected data from 749 women with previous GDM (IADPSG criteria) who underwent postpartum OGTT for type 2 diabetes screening between 2011 and 2019. IGR was identified according to ADA criteria. Results: Prevalence of IGR was 12.7%, lower in women with pre-pregnancy normal weight, higher in women with family history of type 2 diabetes and in those treated with insulin during pregnancy. Prevalence of IGR raised with increasing number of altered glucose values at OGTT performed during pregnancy for GDM screening. HbA1c and triglycerides measured during the third trimester of pregnancy were higher in women with postpartum IGR. At postpartum screening, women with IGR had higher BMI, waist, blood pressure. At multivariate logistic regression analysis, family history of diabetes (OR 2.21; 95% CI: 1.33–3.69; p < 0.01) and presence of all three glucose values exceeding threshold at OGTT during pregnancy (OR 2.89; 95% CI: 1.42–5.86; p < 0.01) were independently associated with IGR. Conclusions: In women with GDM, persistence of IGR in the immediate postpartum period is associated with family history of diabetes and the presence of all three glucose values exceeding diagnostic threshold for GDM at OGTT in pregnancy, suggesting that these women should undergo specific diabetes monitoring and prevention programs.