A randomized trial of prostaglandin E₂ in a controlled-release vaginal pessary for cervical ripening at term

Objective: The purpose of this study was to determine if prostaglandin E₂ in a controlled-release vaginal pessary can produce cervical ripening at term. Study design: This was a double-blind, randomized, placebo-controlled study conducted at a university center and involving 81 patients with 42 receiving active agent. Categoric data were analyzed by Pearson's ζ² or logistic regression. Continuous variables were analyzed by analysis of variance and the F test. Results: Prostaglandin E₂ was significantly better than placebo at cervical ripening and at decreasing the time to rupture of membranes, the time to onset of labor, the need to give oxytocin, and the time to vaginal delivery. Multiparous women benefitted more than primiparous ones. The cesarean section rate decreased only for multiparous women. Uterine hyperstimulation occurred only with prostaglandin E₂ and after the onset of labor. Conclusions: Prostaglandin E₂, when administered in a controlled-release vaginal pessary, is affective in producing cervical ripening at term. This agent should be used on inpatients who are under continuous monitoring and it should be removed at the onset of labor.