Comparative cost analysis of prostaglandin analogues dinoprostone and misoprostol as labor preinduction agents

Objective: To compare the relative cost efficacy of three commercially available prostaglandin analogues, misoprostol (Cytotec®, PGE₁), dinoprostone gel (Prepidil®, PGE₂), and dinoprostone pessary (Cervidil®, PGE₂), as labor preinduction agents.Methods: The investigation was conducted as a prospective randomized, blinded phase III clinical trial. One hundred twelve gravid females undergoing induction of labor with an unfavorable cervix (Bishop score ≤5) were enrolled and randomized to receive either Cytotec® 50 μg q6 hours × 2 doses, Prepidil® 0.5 mg q6 hours × 2 doses, or Cervidil® 10 mg × 1 intravaginally. Twelve hours after initial treatment, cervical Bishop score was reassigned by the same blinded initial examiner and oxytocin induction initiated per standardized protocol. Therapeutic efficacy and cost of the labor preinduction/induction with the study treatments were compared. Statistical comparisons between groups were made using ANOVA with Bonferroni post test, Wilcoxon rank sum test, and χ² test.Results: The three study groups did not differ significantly with respect to parity, gestational age, indication for induction, or initial cervical Bishop score. A significantly greater proportion of patients had a favorable cervix (Bishop score ≥6) after the initial preinduction interval in the Cytotec® (79.0%) and Cervidil® groups (60.5%) as compared to Prepidil® (40.0%) (P < .05). The average relative cost per patient for prostaglandin preinduction was significantly less with Cytotec® ($0.42) as compared to both Cervidil® ($168.00) and Prepidil® ($184.17) (P < .0001). A greater percentage of patients treated with Cytotec® (42.1%) achieved active labor and delivered without the use of oxytocin when compared to Cervidil® (15.8%) or Prepidil® treatment groups (2.9%) (P < .05). Additionally, time to delivery (±SD) was significantly shorter in the Cytotec® group (24.0 ± 10.8 h) as compared to the Cervidil® (32.2 ± 14.7 h) or Prepidil® groups (33.9 ± 16.2 h) (P < .05). This reduction in time resulted in a significantly lower overall mean cost per patient incurred by labor induction in the Cytotec® group ($723.66) as compared to the Cervidil® ($1058.90) or Prepidil® treatment ($1124.84) (P < .01). No significant differences were noted with respect to rate of cesarean delivery.Conclusion: Misoprostol is more cost-effective than the comparable commercial dinoprostone prostaglandin preparations as an adjuvant to labor induction in patients with an unfavorable cervix.