Maternal hypoglycemia on 50 g glucose challenge test: outcomes are influenced by fetal gender.

Objective: To assess the perinatal outcomes in pregnant women with maternal hypoglycemia following a second trimester oral glucose challenge test (GCT).

Materials And Methods: This retrospective case control study consisted of 2091 pregnant women with hypoglycemia (glucose levels >88 mg/dL 1 h following a 50 g GCT in the second trimester of pregnancy) and a control group of 2091 pregnant women with a GCT result between 88 and 130 mg/dL. Perinatal and neonatal characteristics obtained from electronic medical records were compared between groups.

Results: The rates of pregnancy complications were similar in both groups, with the exception of a lower incidence of polyhydramnios and a higher rate of deliveries before the 34th week of gestation in patients with hypoglycemia (0.5% vs. 1.1%, P=0.016 vs. 2.6% vs. 1.7%, P=0.033); respectively. Neonates born to mothers with hypoglycemia had significantly less birth trauma (0.3% vs. 0.9%, P=0.027) and neonatal hypoglycemia. When the data for male and female infants were analyzed separately, male infants had a 1.5-fold (95% CI: 1.05-2.18) increased chance of being small for gestational age (SGA), whereas the risk for female infants did not increase (OR: 0.79, 95% CI: 0.56-1.11).

Conclusion: A low maternal plasma glucose level on the GCT is associated with favorable outcomes, such as decreased rates of birth trauma and neonatal hypoglycemia. In addition, male infants have a higher risk of being SGA than female infants when maternal GCT results were <88 mg/dL.