This study aims to examine the effect of intrapartum treatment of diabetic women with combined glucose and constant insulin infusion compared to glucose alone on the incidence of neonatal hypoglycemia. Pregnant women with diabetes in pregnancy will be randomly divided during labor to 2 groups: group 1, will receive intravenous glucose with constant insulin infusion; group 2 will receive intravenous glucose alone. The primary outcome is the incidence of neonatal hypoglycemia.

About 2 to 9% of pregnant women are diagnosed with gestational diabetes. Peripartum complications attributed to diabetes include: birth trauma, neonatal hypoglycemia and hyperinsulinemia and neonatal hyperbilirubinemia. The incidence of neonatal hypoglycemia is about 40%. Strict glycemic control may lower the risk of neonatal complications. There is a lack of evidence on how to manage women with diabetes during labor. Previous studies recommended the use of intravenous saline solution boosted with 5% glucose and insulin as needed, glucose 5% with constant insulin infusion and others recommended the use lactated Ringer's solution. Most of these studies are either retrospective or have a small number of participants.

In this study we will examine the effect of 2 different protocols on glycemic control during labor and the immediate neonatal period. Women in group 1, will receive intravenous saline solution boosted with 5% glucose and constant insulin infusion. Women in group 2, will receive intravenous saline solution boosted with 5% glucose alone. The desirable intrapartum glucose level will be 70 to 100 mg/dL. Glucose levels will be checked hourly. Women in both groups will receive additional insulin infusion in cases of glucose levels above 100 mg/dL. Additionally, the 5% glucose solution will be substitute with lactated Ringer's solution in cases of glucose levels above 140 mg/dL.

Intravenous fluid regimens will be assigned according to a computer randomization sequence generation program. Women will randomly assigned to the 2 groups in a 1:1 ratio. The randomization sequence results will be kept in the delivery ward in a closed study box. Site investigators will enroll participants after confirming eligibility. The sequence will be concealed until intervention is assigned (and after obtaining a signed informed consent).

Our hypothesis is that 5% glucose combined with constant insulin infusion will achieve better glycemic control and thus will lead to lower rate of neonatal hypoglycemia. In order to detect a reduction of neonatal hypoglycemia from 40% to 20%, 182 women will be needed in both groups in order to achieve a level of significance of 95% (α, 2-sided = 0.05) and a power of 80% (β = 0.2).

Inclusion Criteria:

• >37 weeks gestation
• gestational diabetes mellitus according to Carpenter and Coustan
• pregestational diabetes mellitus

Exclusion Criteria:

• Intrauterine fetal death
• estimated fetal weight<10p
• multiple gestation
• major fetal malformations