Pregnancies complicated by T1D have more glycemic variability than pregnancies associated with other kinds of diabetes. We examined whether remote monitoring of Continuous Glucose Monitoring (CGM) data by family/friends affects glycemic variability during pregnancy.

Women with T1D were stratified to groups during preconception or the 1st trimester: (1) CGM Alone (n=13): women without Apple devices, or (2) CGM Share (n=15, DexCom, San Diego, CA): women with iPhone and followers with data viewing devices. Data within 12 hours of acetaminophen use were excluded. Linear mixed models were used to compare indices of glycemic variability over time between groups.

A1C decreased in both groups over time and was lower in CGM Share compared to CGM Alone (p=0.0376, Table). Mean sensor glucose was lower in CGM Share than CGM Alone (p=0.0492). Times spent within targeted pregnancy ranges were not different between groups. CGM Alone had a significantly higher High Blood Glucose Index (HGBI) than CGM Share (p=0.0347).

CGM Share was associated with a lower risk of hyperglycemia (as measured by HBGI) than CGM Alone among pregnant women with T1D, but other measures of glycemic variability were similar between groups.

S. Polsky: Consultant; Self; Jaeb Center for Health Research. Research Support; Self; Barbara Davis Center for Diabetes, Children's Diabetes Foundation, Dexcom, Inc., Eli Lilly and Company, JDRF, Leona & Harry Helmsley Charitable Trust, National Institute of Diabetes and Digestive and Kidney Diseases, Sanofi US. J.K. Snell-Bergeon: None. P. Joshee: None. J.K. Demmitt: None. R. Garcetti: None. T.B. Vigers: None. L. Pyle: None.


Dexcom, Inc.; National Center for Research Resources/Colorado Clinical and Translational Science Institute (UL1RR025780)

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