Background: Diabetes in pregnancy portends increased maternal and fetal morbidity and mortality. Glucose testing is advised at 1 or 2 hours Pp. CGM during pregnancy may improve meal-time glycemic monitoring. Limited Pp CGM data exist for gestational diabetes (GDM), type 1 diabetes (T1D), or type 2 diabetes (T2D).

Methods: We report prospective Pp glycemic data for 32 pregnant women collected during a 6-hour YSI clinic session for a 10-day Dexcom G6 CGM accuracy trial. Each subject wore 2 sensors. During the session, food consumption was recorded and analyzed if >5g. Meals were not standardized. CGM and YSI Pp responses within 2 hours of meals and carbohydrate content were evaluated.

Results: Most women had T1D (n=20) (See table). Subjects consumed 1 (n=6), 2 (n=13) or 3 (n=13) meals for a total 71 meals. Mean carbohydrate intake per meal was 29 ± 19 g (range 6-101). Peak CGM values were recorded for 32 morning and 31 afternoon meals in 2 sensors/subject (n=139 values). Pp CGM values peaked at 136 ± 32 mg/dL (range 78-233) at median 60 minutes (interquartile range: 44, 99).

Conclusions: Eating patterns are heterogeneous among pregnant women. These data support 1 hour Pp testing, and CGM use allows more detailed glycemic evaluations around meals. Our YSI results support CGM reliability. Timing of Pp peak glucose levels related to nutrient content in pregnancy needs further evaluation.


E.V. Nosova: None. K.N. Castorino: Research Support; Self; Abbott, Dexcom, Inc., Medtronic, Mylan, Novo Nordisk Inc. C.J. Levy: Consultant; Self; Dexcom, Inc. Employee; Spouse/Partner; Allergan plc. Research Support; Self; Abbott, Dexcom, Inc., Insulet Corporation. T. Johnson: 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. C. Levister: None. S.J. Brackett: None. S. Polsky: None.

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