Continuous Glucose Monitoring (CGM) Profiles in Pregnancies with and without Gestational Diabetes Mellitus

Objective: To determine if continuous glucose monitor (CGM)-derived glycemic patterns can characterize pregnancies with GDM as diagnosed by standard oral glucose tolerance test at 24-28 weeks’ gestation compared to those without GDM. Research Design and Methods: The analysis includes 768 individuals enrolled from two sites prior to 17 weeks’ gestation between June 2020 and December 2021 in a prospective observational study. Participants wore blinded Dexcom G6 CGM throughout gestation. Main outcome of interest was a diagnosis of GDM by oral glucose tolerance test (OGTT). Glycemic levels in participants with GDM vs. without GDM were characterized using CGM-measured glycemic metrics. Results: Participants with GDM (n=58 8%) had higher mean glucose (109±13 vs. 100±8 mg/dL 6.0±0.7 vs. 5.6±0.4mmol/L, p120 mg/dL (>6.7mmol/L) (median 23% vs. 12%, p140 mg/dL (>7.8mmol/L) (median 7.4% vs. 2.7%, p120 mg/dL (>6.7mmol/L) and time >140 mg/dL (>7.8mmol/L) were higher as early as 13-14 weeks’ gestation (32% vs. 14%, p