Comparative efficacy and cost of the prostaglandin analogs dinoprostone and misoprostol as labor preinduction agents

OBJECTIVE: The purpose of this study was to compare the relative efficacy and cost of three commercially available prostaglandin analogs, misoprostol (Cytotec), dinoprostone gel (Prepidil), and dinoprostone insert (Cervidil), as labor preinduction agents. STUDY DESIGN: One-hundred eleven women with an unfavorable cervix who underwent labor induction were assigned randomly to receive either misoprostol 50 μg every 6 hours for two doses, dinoprostone gel 0.5 mg every 6 hours for two doses, or dinoprostone insert 10 mg for one dose intravaginally. Twelve hours later, oxytocin induction was initiated per standardized protocol. Efficacy and cost of the labor preinduction/induction with the study treatments were compared. RESULTS: Mean Bishop score change (±SD) over the initial 12-hour interval was significantly greater in the misoprostol group (5.2 ± 3.1) compared with the dinoprostone insert (3.2 ± 2.3) or the dinoprostone gel groups (2.2 ± 1.3, P < .0001). The proportion of women who reached complete dilation (68.4%, 50.0%, 51.4%, respectively; P= .14) and who were delivered (60.5%, 47.4%, 40.0%, respectively; P= .10) within 24 hours of the initiation of induction were not significantly different between the misoprostol, dinoprostone insert, and dinoprostone gel groups. Induction-to-delivery intervals, however, were significantly shorter among women who treated with misoprostol (24.0 ± 10.8 hours) compared with either the dinoprostone gel (31.6 ± 13.4 hours) or the dinoprostone insert (32.2 ± 14.7 hours, P < .05). Overall mean cost per patient that was incurred by labor induction was significantly less for the misoprostol group ($1036.13) compared with the dinoprostone insert group ($1565.72) or the dinoprostone gel group ($1572.92, P < .0001). No significant differences were noted with respect to the mode of delivery or to the adverse maternal/neonatal outcome. CONCLUSION: Misoprostol is more cost-effective than the comparable commercial dinoprostone prostaglandin preparations as an adjuvant to labor induction in women with an unfavorable cervix.