Objective: To evaluate the effect of early amniotomy in term gestation on the mode of delivery and pregnancy outcome in comparison with premature rupture of membranes (PROM) and oxytocin induction.
Study design: The study population consisted of 60 consecutive parturients induced by early amniotomy. The two comparison groups were 147 women admitted with term PROM and 65 patients induced by oxytocin. All study participants were evaluated prospectively and had unfavorable cervical scores.
Results: The duration of the first stage of labor was significantly longer in the PROM group (987.8 +/- 572.3 min) as compared with the early amniotomy group (615.0 +/- 389.6 min) and the oxytocin induction group (650.9 +/- 349.5 min, P<0.001). Higher rates of CS were found in the study group (26.7%) as compared to the controls (11.6% in the PROM and 16.9% in the oxytocin groups, p=0.012). Neonatal outcome was similar in all groups. A stratified analysis comparing the risk of CS while controlling for a previous one did not show a significant difference between the early amniotomy and the oxytocin administration groups.
Conclusions: Early amniotomy is associated with a higher rate of CS. While controlling for a previous CS, both ways of induction were comparable. In order to decrease the CS rates, induction should probably start with cervical ripening techniques in order to improve the Bishop scores.