Iatrogenic Fetal Hypoglycemia Following Tight Peripartum Glucose Control in Diabetic Mothers: A Hypothesis and a Case Report

Abstract Current management of diabetes in pregnancy includes prompt normalization of glucose prior to delivery in women with poorly controlled diabetes. While the benefits of glucose control throughout pregnancy are well-documented, the benefits of rapid glucose normalization prior to delivery are borderline. There is a lack of information on the fetal effects of this practice. There is a concern that a rapid decrease in maternal glucose level could cause hypoglycemia in the fetus, developing in the same manner as in a newborn infant of a mother with diabetes. This case highlights a 37 week infant of a mother with poorly controlled diabetes, whose mother's glucose was normalized with intravenous insulin 24 hours before delivery. The infant's arterial cord blood glucose was 2.1 mmol/L, indicative of hypoglycemia, and it required neonatal intensive care unit admission. Current guidelines emphasize tight peripartum glycemic control but overlook potential fetal hypoglycemia before birth. This case suggests fetal hypoglycemia may precede neonatal hypoglycemia, with similar risks but limited diagnostic opportunities. Further research is needed to evaluate fetal outcomes of stringent glycemic control and to establish early cord blood glucose monitoring to improve the identification and management of hypoglycemia in this vulnerable population.