MiniMed^TM 780G Advanced Hybrid Closed-Loop System Study in Pregnant Women with Type 1 Diabetes

Background: Evaluate the impact of the MiniMed™ 780G advanced hybrid closed-loop (AHCL) system on the glucose profile of pregnant women with type 1 diabetes (T1D) and maternal-neonatal complications. Methods: From April 2021 to September 2022, pregnant women with T1D treated with the AHCL system were included in an observational multicenter retrospective study. Continuous glucose monitoring parameters were analyzed monthly during pregnancy as well as maternal-neonatal complications. Results: Thirteen pregnant women, including a twin pregnancy (age: 33 ± 3 years, hemoglobin A1c [HbA1c]: 7.3% ± 0.7%, insulin doses: 0.72 ± 0.21 U/kg/day) were analyzed. At delivery, gestational age was 37 ± 2 weeks. During first 2 weeks of pregnancy, time in range (TIR, 63-140 mg/dL) was 46% (34-55) and increased to 54% (51-59) (P < 0.01), 64% (48-68) (P < 0.01), and 66% (60-70) (P < 0.001) during the first, second, and third trimester, respectively. During the night, TIR (63-140 mg/dL) was >70% throughout pregnancy. Time below the range <63 mg/dL increased from 0.5% (0-2) to 1.3% (0.7-2.2), 2% (1.2-3.5) (P < 0.05), and 1.3% (1.31-3) (P < 0.05) during the first, second, and third trimester, respectively. At delivery, insulin doses increased to 0.89 ± 0.35 IU/kg/day (P < 0.01), and HbA1c decreased to 6.4% ± 0.6% (P = 0.005). The reported carbohydrate amount increased from 167 ± 363 g/d during early pregnancy to 243 ± 106 g/d (P < 0.01) at delivery. The birthweight was 3134 ± 711 g, with 5/14 macrosomia and 2/14 neonatal hypoglycemia. Moreover, 5/13 patients had a preeclampsia and 9/13 a cesarean section, including three cases of scarred uterus. The Clinical Trial Registration number is: CE-2022-55. Conclusion: The AHCL system provided good glucose control during pregnancy and recommendation targets were reached during the nocturnal period only. The maternal and neonatal complications remained high.