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The efficacy of early amniotomy in nulliparous labor induction: a randomized controlled trial
George A Macones1, Alison Cahill, David M Stamilio
1Department of Obstetrics and Gynecology, Washington University in St. Louis School of Medicine, St. Louis, MO 63110, USA. maconesg@wustl.edu
Objective:
The purpose of this study was to assess whether early amniotomy reduces the duration of labor or increases the proportion of subjects who are delivered within 24 hours in nulliparous patients who undergo labor induction.
Study Design:
We performed a randomized controlled trial that compared early amniotomy to standard management in nulliparous labor inductions. Inclusion criteria were nulliparity, singleton, term gestation, and a need for labor induction. Subjects were assigned randomly to early amniotomy (artificial rupture of membranes, ≤4 cm) or to standard treatment. There were 2 primary outcomes: (1) time from induction initiation to delivery and (2) the proportion of women who delivered within 24 hours.
Results:
Early amniotomy shortens the time to delivery by >2 hours (19.0 vs 21.3 hours) and increases the proportion of induced nulliparous women who deliver within 24 hours (68% vs 56%). These improvements in labor outcomes did not come at the expense of increased complications.
Conclusion:
Early amniotomy is a safe and efficacious adjunct in nulliparous labor inductions.
