The purpose is to determine in term nulliparas with singletons that present in active labor (3-5 cm) or with ruptured membranes whether the administration of dextrose solutions to normal saline improves or expedites the course of labor. The researchers' hypothesis is that the addition of a carbohydrate substrate will shorten the length of labor and facilitate a vaginal delivery.

Factors that affect the course of labor have been studied extensively. Surprisingly, there is little data on the effect that different types and rates of intravenous (IV) fluids have during labor. Exercise physiologists have shown that increased fluid intake and carbohydrate replacement improve skeletal muscle performance in prolonged exercise. In a 1992 randomized, controlled study comparing IV fluid rates, Garite et al. showed a lower frequency of prolonged labor, and possibly a decreased need for oxytocin, with higher IV fluid rates in labor. Inadequate hydration may contribute to dysfunctional labor and possibly an increased rate of cesarean section.

We propose that inadequate carbohydrate replacement in labor may also contribute to prolongation of labor and increased need for operative delivery. Glucose is the main energy supply for the pregnant uterus. Physiological requirements for glucose during labor are approximately 10 grams per hour. Adequate supplies of glucose are needed to maintain exercise tolerance and muscle efficiency, which are important factors in the progress of labor. Dysfunctional labor or dystocia, which is the leading indication for primary cesarean delivery, is caused by uterine forces insufficiently strong or inappropriately coordinated to efface and dilate the cervix. Dystocia can also be a result of inadequate voluntary muscle effort in the second stage of labor. It contributes to increased risk for chorioamnionitis, which is a leading cause of maternal and fetal morbidity and mortality. Supplying carbohydrate fuel for working uterine and skeletal muscle may improve progress in labor and, therefore, diminish risk for chorioamnionitis and need for cesarean delivery.

• Primiparous
• Singleton gestation
• Vertex presentation
• Spontaneous active labor with or without pitocin augmentation
• Gestational age > 36 weeks
• Cervical dilation 3 to 5 cm with or without ruptured membranes

Exclusion Criteria:

• Multiparous
• Pregestational or gestational diabetes mellitus
• Preeclampsia at admission
• Previous cesarean section
• Non-vertex presentation
• Multiple gestation
• Chorioamnionitis at admission
• Intrauterine growth restriction (< 10th percentile)
• Patients admitted for induction