Effects of Maternal Gestational Diabetes on Neonatal Hypoglycemia: Diet vs Insulin Treatment

The neonatal infants born to women treated with insulin compared with noninsulin (diet-controlled) for the management of gestational diabetes may not experience any difference in the incidence of mild and severe hypoglycemia, according to a study published in Diabetes Care.

Researchers conducted a prospective cohort study from January 2013 to December 2015 at the University Medical Center Utrecht in the Netherlands, where they identified 506 neonates born to mothers diagnosed with gestational diabetes treated with noninsulin (n=392, 77.5%) and with insulin (n=114, 22.5%).

Glucose levels were measured in neonates at 1, 2, 6, 12, and 24 hours after birth, with all testing performed before feedings.

The purpose of the study was to assess the risk for neonatal hypoglycemia in neonates born to women with gestational diabetes treated with either noninsulin or insulin, and to determine whether there were any associations relative to birth weight. Hypoglycemia measures of mild and severe hypoglycemia were defined as ≤47 mg/dL and ≤36 mg/dL, respectively.

Researchers found incidences of both mild and severe hypoglycemia to be very similar between women with gestational diabetes treated with insulin compared with those treated with noninsulin (diet-controlled) (33% vs 35% [P =.66] and 20% vs 21% [P =.79]), with the overall incidence of both mild and severe hypoglycemia for all infants being 33.4% and 20.2%, respectively. The majority of hypoglycemic events were identified in children born with a birth weight <90th percentile despite there being a higher risk for hypoglycemia in those with a birth weight >90th percentile (17.2% of study subjects).

In regard to timing of hypoglycemic events, the first few hours after birth identified the large majority of both mild and severe hypoglycemia events, with 66.3% of mild and 81.4% of severe hypoglycemia identified within the first hour after birth. A plateau in the identification of hypoglycemia events was reached at approximately 12 hours after birth, as 96.5% and 98% of mild and severe incidents, respectively, had been identified by that time.

Researchers concluded that there was a high incidence of mild and severe hypoglycemia events in neonates born to mothers diagnosed with gestational diabetes treated with either insulin or noninsulin, with incidences of neonatal hypoglycemia events occurring within the first 12 hours of life regardless of maternal insulin or birth weight. Therefore, neither insulin nor a noninsulin treatment plan for gestational diabetes was found to be superior to the other, or with reduced neonatal hypoglycemic events, and both can be used when appropriate to treat gestational diabetes. Clinicians are encouraged to continue to monitor closely neonates born to women with gestational diabetes within the first 12 hours of life regardless of birth weight or treatment with insulin, as these neonates are at a high risk for hypoglycemia.

Reference

Voormolen DN, de Wilt L, van Rijn BB, et al. Neonatal hypoglycemia following diet-controlled and insulin-treated gestational diabetes mellitus [published online April 13, 2018]. Diabetes Care. doi: 10.2337/dc18-0048