Characteristics of oral prostaglandin E2-induced labor.

Oral prostaglandin E2 appears to play a dual role in human parturition. It induces normal uterine contractions and softens the cervix, thereby decreasing the resistance of the cervix to dilatation. Labor and delivery with oral PGE2 is achieved with less total uterine work when compared with spontaneous nonstimulated labor. This contention is supported by the fact that the rate of cervical dilatation in the active phase of labor is faster (2.73 cm/hr) than that reported by Hendricks et al. for ideal labor (2.12 cm/hour), yet uterine contractility is not increased. Analysis of the composite data of Friedman and Sachtleman in 1974 also shows a more rapid active phase dilatation in the PGE2-stimulated labors (3.3 cm/hour) as compared with spontaneous labor (2.98 cm/hour). Oral PGE2 offers a safe and efficacious alternative to oxytocin for the induction of labor in women. It appears to have a major advantage over oxytocin. The softening effect of PGE2 on the cervix would make this drug an ideal agent for use in patients with low Bishop scores who have medical indications for induction of labor. Regardless of route of administration, prostaglandin E2 is a potent uterine stimulant and must be used with the same precautions and safeguards as intravenous oxytocin.