Relationship between continuous maternal intrapartum and postpartum glucose monitoring metrics and neonatal outcomes and postpartum glucose metabolism in individuals with gestational diabetes

Continuous glucose monitoring (CGM) improves maternal and neonatal outcomes in pregnancies complicated by preconception diabetes. CGM measurements may help optimize intrapartum and postpartum glycemic management in pregnant women with GDM. We investigated the use of blinded CGM-derived metrics during labor, delivery, and postpartum supplementary to normally monitored glucose measures in women with GDM to study neonatal outcomes and postpartum glucose metabolism. This prospective observational study evaluated 60 pregnant women with gestational diabetes mellitus (GDM) during the peripartum and postpartum periods. Of these, 35% were managed with diet alone, while 65% required pharmacologic therapy (insulin, metformin, or both). Participants wore a blinded continuous glucose monitor (Dexcom G6 Pro) for 10 days, beginning 1–3 days before delivery. At 6–18 weeks postpartum, all underwent a 75-g oral glucose tolerance test (OGTT), with a subset (n = 28) also using blinded CGM. Univariate and logistic regression analyses assessed associations between CGM metrics in the 24 h preceding delivery and neonatal hypoglycemia or NICU admission. Infants of women having an induced vaginal or unplanned caesarean delivery (C-section) were significantly more likely than infants delivered by repeat C-section to have neonatal hypoglycemia (p = 0.005). No significant correlations between maternal CGM-derived metrics and postnatal adaptation in the newborn were found and none of the models trained to predict neonatal hypoglycemia or intensive unit (NICU) admission showed satisfactory power. While only modest associations between postdelivery CGM metrics and postpartum OGTT values were observed, there were strong correlations between postpartum CGM metrics and OGTT-derived values. In GDM, intrapartum CGM-based metrics were not associated with adverse neonatal outcomes. Future investigations with a larger cohort are needed to assess intra-and postpartum CGM-metrics in women with GDM and their association with neonatal outcomes and OGTT results. ClinicalTrials.gov, NCT05067075 (initiation 11/1/2021).