Introduction: Up to 50% babies born from women affected by type 1 diabetes mellitus (T1DM) present perinatal complications, such as macrosomia, large abdominal circumference, preterm birth, neonatal hypoglycemia and admission to neonatal ICU. Maternal hyperglycemia is the main risk factor for the insurgence of such complications, and most pregnant women with T1DM fail to achieve the recommended glycemic targets. The use of continuous glucose monitoring (CGM) and hybrid closed loop systems (HCLS) is associated with a higher time in range (TIR) percentage, especially if started before 16 weeks’ gestation. During labor and delivery insulin is administered by variable rate intravenous insulin infusion (VRIII) or continuous subcutaneous insulin infusion (CSII). At time of delivery, a dramatic reduction in insulin requirement occurs in a scarcely predictable way. HCLS may be useful in such a quick adjustment of insulin doses in the postpartum period. However, data on their use during labor, delivery and postpartum are scarce. We decided to describe the use of advanced HCLS Medtronic Minimed 780 G in a 18 year-old pregnant patient with T1DM during labor, delivery and postpartum. Case: The patient was diagnosed with T1DM in 2018; she had advanced HCLS Medtronic Minimed 780 G positioned in 2022. In February 2023 she started an unplanned pregnancy and kept the HCLS in place, being followed weekly and reaching a better glycemic control (HbA1c from 7.7% to 6.9%). In October 2023 she gave birth to a normosomic baby at 37 weeks gestation, with no major peri- or postnatal complications for the mother or the baby. The patient kept the HCLS in place during labor, delivery and post-partum, with a glycemic target of 100 mg/dl. The data show a 87% TIR and a mean glycemia of 108 mg/dl. The automated system quickly adapted to the reduction in insulin requirement after delivery, preventing major hypoglycemias with no dramatic changes in glycemic variability (CV 30.1%). Conclusions: This case report demonstrates the potential advantages of advanced HCLS during labor, delivery and post-partum. As the beneficial effects of the system during pregnancy have already been acknowledged, its use during delivery is still limited. Its flexibility and velocity in auto-learning make it suitable for the quick setting changes required during labor and post-partum, ameliorating glycemic profiles of T1DM patients during delivery with no need for VRIII or CSII.
