Glycemic control varies among different cohorts of pregnant women with diabetes. Most studies examining differences between groups using continuous glucose monitoring (CGM) data were performed with older CGM systems worn for 2-7 days. We examined differences in glycemic control and glycemic variability (GV) between pregnant women (n=32) with T1D (n=20), T2D (n=3), or GDM (n=9) in the 2nd and 3rd trimesters using the Dexcom G6 CGM system, worn for 10 days as part of a pregnancy CGM accuracy trial. Pair-wise comparisons were made between groups and group heterogeneity testing was performed. No adjustments were made for multiple comparisons analyses. Most women required insulin therapy (26/32, 81%). The baseline HbA1C levels were similar between groups (Table). The glucose management indicator (GMI) was numerically similar to HbA1C for the T1D and GDM cohorts. Time spent >140 mg/dL (p=0.009) was highest and time in range (63-140 mg/dL) was lowest (p=0.001) in women with T1D compared to the other groups. The coefficient of variation (CV) and mean amplitude of glycemic excursions (MAGE) were highest in the T1D group, lowest in the GDM group, and intermediate in the T2D group (p<0.0001 for each). Glycemic control was better and GV was lower for pregnant women with T2D and GDM compared to women with T1D. CGM use in pregnancy helps elucidate GV.


S. Polsky: None. C.J. Levy: Consultant; Self; Dexcom, Inc. Employee; Spouse/Partner; Allergan plc. Research Support; Self; Abbott, Dexcom, Inc., Insulet Corporation. X. Zhang: Employee; Self; Dexcom, Inc. S. Shah: Employee; Self; Dexcom, Inc. G. Haroush: None. K. Nelson: None. G. O’Malley: Research Support; Self; Abbott, Dexcom, Inc. S.J. Ogyaadu: None. S.J. Brackett: None. C. Levister: None. K.N. Castorino: Research Support; Self; Abbott, Dexcom, Inc., Medtronic, Mylan, Novo Nordisk Inc.


Dexcom, Inc.

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