Maternal and fetal outcomes in a retrospective cohort of obstetrical patients that used an insulin pump paired with a continuous glucose monitor.

OBJECTIVE: To assess maternal and neonatal outcomes in pregnant pregestational diabetic patients using a continuous subcutaneous insulin infusion (CSII) pump paired with a continuous glucose monitor (CGM).

METHODS: This retrospective cohort study included 55 patients who delivered within one healthcare system from October 2019 to October 2022 with pregestational diabetes managed using CSII pumps paired with CGM. Maternal blood glucose (BG) data were analyzed for the two-week period preceding delivery. The percentage of time spent at a BG level of less than 140 mg/dL was recorded and compared between patients with and without obstetric and neonatal morbidities.

RESULTS: Patients who delivered with severe preeclampsia (S. PreE) had a significantly lower mean percentage of time spent at BG < 140 mg/dL than those who did not (S. PreE 15/55, 63.1% ± 19.0 vs. 40/55, 73.6% ± 13.8; p  = 0.03). Mothers who had a preterm birth (PTB) had a significantly lower mean percentage of time spent at BG < 140 mg/dL than those who delivered at term (PTB 35/55, 66.4% ± 16.4 vs 20/55, 78.3% ± 11.9; p  = 0.006). The mean percentage of time spent at a BG < 140 mg/dL among mothers of neonates with respiratory distress syndrome (RDS) was significantly lower than those without RDS (RDS present 13/55, 59.7% ± 20.4 vs 42/55, 74.1% ± 12.7; p  = 0.003). There was a significant correlation between a greater neonatal birth weight percentile and worse time spent at BG < 140 mg/dL (r = - 0.31; p  = 0.02). No other significant differences were observed between the groups.

CONCLUSION: Improved blood glucose levels in pregestational diabetic patients using a CSII pump and CGM is associated with reduced maternal and neonatal morbidity as well as lower birth weight percentile neonates. Future studies are needed to clarify how much time each day a patient needs to spend below a given blood sugar, how long this blood glucose should be maintained, and what specific blood glucose target should be selected.