Continuous glucose monitoring profiles during postpartum glucose tolerance test results among people with gestational diabetes

Abstract Objective Current guidance recommends universal screening with a postpartum oral glucose tolerance testing (OGTT) 4–12 weeks following delivery among pregnancies complicated by gestational diabetes mellitus (GDM) to identify or assess risk for prediabetes and type 2 diabetes (T2D). Continuous glucose monitoring (CGM) is not currently a tool for screening for T2D among pregnant or postpartum people. Our objective was to assess CGM data during the postpartum OGTT. Methods This was a secondary analysis of a trial that randomized people with GDM to CGM versus capillary blood glucose (CBG). Participants were included if CGM data were available during their OGTT. Our primary outcome was mean glucose during the postpartum OGTT (75 g 2‐h challenge), comparing those with dysglycemia on OGTT (fasting ≥100 mg/dL and/or 2‐h ≥140 mg/dL) to normal OGTT results. Results A total of 51 patients met the inclusion criteria for this secondary analysis. Mean CGM glucoses were higher at all time points for those with dysglycemia compared with a normal OGTT result. Among those with dysglycemia, the mean fasting plasma glucose was 104.3 ± 10.5 and the mean 2‐h plasma glucose was 129.9 ± 37.5. For those with normal OGTT results, the mean fasting plasma glucose was 89.8 ± 5.2 and the mean 2‐h plasma glucose was 103.5 ± 17.9. When stratified by GDM type, mean CGM glucose was similar between groups. Conclusion In this study, we found that glucose measured by CGM follows the expected curve in response to the postpartum OGTT among individuals with pregnancies complicated by GDM. Those with dysglycemia had higher mean CGM glucose at all time points assessed. Future studies will need to assess the role of CGM in risk stratifying those with dysglycemia postpartum without an OGTT.