Objectives: An optimized metabolic control during delivery is mandatory to prevent maternal-neonatal complications. The primary aim of this study was to evaluate the efficacy and safety of continuous subcutaneous insulin infusion (CSII) during delivery in pregnant women with type 1 diabetes. The secondary aim was to assess the impact of real-time continuous glucose monitoring (RT-CGM) added to CSII versus CSII alone.
Research design and methods: This was a multicenter observational retrospective study. A standardized protocol, to use CSII throughout pregnancy and delivery, foresaw three different insulin basal rates according to blood glucose level: profile A, the last basal rate in use; profile B, preventive 50% reduction of the last basal rate in use; and profile C, 0.1-0.2 U/h for blood glucose level <70 mg/dL, activated just before anesthesia or at the beginning of active labor. An alternative intravenous protocol (IVP) was given in case of complications and relevant metabolic deterioration. Blood glucose in the target range (70-140 mg/dL) throughout delivery and percentage of activation of the IVP were primary outcomes.
Results: Sixty-five pregnant women with diabetes included in the study (56-86% cesarean section; 9-14% spontaneous/stimulated vaginal delivery). Mean blood glucose level was 102 ± 31 mg/dL at 0 min, 109 ± 42 mg/dL at 30 min, 120 ± 48 mg/dL at 60 min, and 99 ± 34 mg/dL at 24 h. Mean basal rate during delivery was 0.6 ± 0.4 U/h (profile B). Mean capillary blood glucose (CBG) level was lower in the RT-CGM group relative to the CSII-alone group: 80 ± 14 mg/dL versus 111 ± 32 mg/dL at 0 min (P<0.01), 79 ± 11 mg/dL versus 109 ± 42 mg/dL at 30 min (P<0.02), and 98 ± 20 mg/dL versus 125 ± 51 mg/dL at 60 min (difference not significant). Eleven newborns experienced transient neonatal hypoglycemia. None of the women switched to IVP. No major differences were observed according to delivery procedure.
Conclusions: CSII is possible and safe in different types of delivery in selected and educated women. RT-CGM helps to obtain better outcomes in terms of maternal peripartum CBG level.