Reexamining intrapartum glucose control in patients with diabetes and risk of neonatal hypoglycemia.

Objective: Compare the incidence of hypoglycemia in neonates born to patients with diabetes, based on last maternal glucose before delivery.

Study Design: Cohort of singleton births from individuals with pregestational and gestational diabetes (GDM) from 2017 to 2019.

Results: We included 853 deliveries. Maternal hyperglycemia before delivery was associated with 1.8-fold greater risk of neonatal hypoglycemia (glucose < 45 mg/dL) in patients with GDM on medication (adjusted risk ratio (aRR): 1.8; 95% CI: 1.1-2.7), compared with euglycemia. This association was not seen in diet-controlled GDM (0.5; 0.23-1.1), nor in Type 1 (1.1; 0.88-1.4), or Type 2 pregestational diabetes (1.1; 0.61-1.9). Further, pregestational diabetes, compared to GDM, regardless of intrapartum maternal glucose control, was associated with neonatal hypoglycemia and NICU admission.

Conclusion: Maternal hyperglycemia before delivery only carried a higher risk of neonatal hypoglycemia in those with GDM on medications. Other interventions to reduce neonatal hypoglycemia are needed.