The Role of Oxytocin in the Second Stage of Labor

Oxytocin is widely used on Labor and Delivery units throughout the world.Laboring patients are most likely to initiate oxytocin in the first stage of labor. Among those who receive oxytocin, first stage initiation is far more common than second stage initiation. The goal of first stage administration is to increase uterine contractility and cause cervical dilation, particularly in patients who have epidural analgesia. Once complete cervical dilation has been achieved, most providers choose to continue oxytocin in the second stage of labor for the theoretic benefit of increased expulsion "power" while pushing. This practice is currently not evidence-based as the limited data thus far suggests no difference in operative deliveries with the use of oxytocin augmentation in general. The benefits and risk of oxytocin continuation in the second stage of labor is unknown. Oxytocin administration is associated with the risk of uterine tachysystole, postpartum hemorrhage,and maternal hyponatremia. These risks call for a closer look at prolonged oxytocin use past the first stage of labor. This is a randomized controlled trial investigating the utility of oxytocin administration in the second stage of labor.

Inclusion criteria

• Nulliparous pregnant women >/= 37 weeks gestation
• Singleton pregnancies
• Admission for induction of labor or spontaneous labor

Exclusion criteria

• Multiple gestations
• Multiparous patients
• Patients with major fetal anomalies
• Not on oxytocin at the time of complete cervical dilation
• Patients with fetal head visible at the perineum on diagnosis of complete cervical dilation
• Maternal medical condition that prohibits prolonged second stage