Pregnancies in type 1 diabetes (T1D) are high-risk, and data in the U.S. are limited regarding clinical and CGM based hypoglycemia throughout pregnancy while on sensor augmented insulin pump (SAP). Pregnant women with T1D on insulin pump ≤ 16 wks gestation were enrolled at 3 U.S. centers and used study Dexcom G6. We analyzed episodes of severe hypoglycemia (SH) and days with > 20 hrs of CGM for biochemical hypoglycemia (BH) based on international consensus guidelines (<63 and <54 mg/dl) and frequency/duration of prolonged hypoglycemia (PH, ≥120 mins < 54 mg/dl) Twenty pregnant subjects, age 31 ± 4.5 yrs, 14 ± 8 yrs of T1D, baseline weight 77 ± 16 kg, BMI 28 ± 6.2 kg/m2, HbA1c 6.5 ± 0.7%, were studied. Gestational age at enrollment and delivery was 11.4 ± 4 and 37.7 ± 1.5 wks respectively. One subject experienced a single episode of SH with an overall incidence 7/100 patient years. Percentage of hypoglycemia and BH events per trimester are described in Table 1. BH was common in each trimester, but most frequent in the first. Eighteen events of PH occurred in four subjects (20%) lasting 120-410 mins with two events each in two, three events in one and 11 events in one subject respectively with 15 (83%) events occurring between 12am-6am. Our study shows pregnant women with T1D on SAP frequently experience level 1 hypoglycemia, and 20% experience prolonged hypoglycemia predominantly overnight.


R. Kaur: None. B.H. Smith: None. J.E. Pinsker: Advisory Panel; Self; Medtronic. Consultant; Self; Eli Lilly and Company, Tandem Diabetes Care. Research Support; Self; Dexcom, Inc., Eli Lilly and Company, Insulet Corporation, Medtronic, Tandem Diabetes Care. Speaker’s Bureau; Self; Tandem Diabetes Care. B. Ozaslan: None. G. O’Malley: Research Support; Self; Abbott, Dexcom, Inc. M. Trinidad: None. D. Desjardins: None. K.N. Castorino: Research Support; Self; Abbott, Dexcom, Inc., Medtronic, Mylan, Novo Nordisk Inc. C. Levister: None. C. Reid: None. S.K. McCrady-Spitzer: None. S.J. Ogyaadu: None. M. Church: None. M. Piper: None. W.K. Kremers: Research Support; Self; AstraZeneca. B. Rosenn: None. C.J. Levy: Consultant; Self; Dexcom, Inc. Employee; Spouse/Partner; Allergan plc. Research Support; Self; Abbott, Dexcom, Inc., Insulet Corporation. E. Dassau: Consultant; Self; Eli Lilly and Company. Research Support; Self; Dexcom, Inc., DreaMed Diabetes, Tandem Diabetes Care, Xeris Pharmaceuticals, Inc. Speaker’s Bureau; Self; Roche Diabetes Care. Other Relationship; Self; Dexcom, Inc., Insulet Corporation, Roche Diabetes Care. Y.C. Kudva: Research Support; Self; Dexcom, Inc., Roche Diabetes Care. Other Relationship; Self; Abbott.


National Institutes of Health (122358); Dexcom, Inc. (AP-2018-016)

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