Objective: We sought to determine if uterine tachysystole, ≥ 6 contractions per 10 minutes, within the first 4 hours of labor induction, is associated with adverse infant outcomes.
Study design: This was a prospective cohort study of 584 women ≥ 37 weeks' gestation undergoing induction of labor with 100 μg of oral misoprostol. Fetal heart rate tracings were analyzed for contractions per 10 minutes during the initial 4 hours after misoprostol administration. Patients were analyzed based on the maximum number of contractions per 10 minutes. Infant condition at birth was assessed using the fetal vulnerability composite.
Results: Adverse infant outcomes showed no association with increasing number of contractions per 10 minutes. Six or more contractions in 10 minutes were significantly associated with fetal heart rate decelerations (P ≤ .001). Analysis was performed using the maximum number of contractions per 30 minutes with similar results.
Conclusion: Uterine tachysystole, as currently defined, when occurring remote from delivery is not associated with adverse infant outcomes.
Copyright © 2012 Mosby, Inc. All rights reserved.