A randomized comparison of home uterine activity monitoring in the outpatient management of women treated for preterm labor

Abstract

Objective: The aim of the study was to evaluate home uterine activity monitoring as an intervention in reducing the rate of preterm birth among women treated for preterm labor. Study Design: A total of 186 women were treated in the hospital with magnesium sulfate for preterm labor and were prospectively randomly assigned to study groups; among these, 162 were ultimately eligible for comparison. Eighty-two of these women were assigned to the monitored group and 80 were assigned to an unmonitored control group. Other than monitoring, all women received identical prenatal follow-up, including daily perinatal telephone contact and oral terbutaline therapy. Outcome comparisons were primarily directed toward evaluation of preterm birth at <35 weeks’ gestation. Readmissions for recurrent preterm labor and observations lasting <24 hours were evaluated in monitored and unmonitored groups. Compliance with monitoring was also evaluated in the monitored group. Results: The monitored and control groups were demographically similar. According to a multivariate logistic regression model, women with cervical dilatation of ≥2 cm were 4 times more likely to be delivered at <35 weeks’ gestation ( P < .05). Gestational ages at delivery were similar in the monitored and control groups. There was no significant difference in the overall rate of preterm delivery at <35 weeks’ gestation between the monitored group (10.9%) and the control group (15.0%). The overall rates of delivery at <37 weeks’ gestation were high (48.8% and 60.0% for monitored and control groups, respectively), and the difference was not significant. The numbers of women with ≥1 instance of readmission and treatment for recurrent preterm labor were equal in the monitored and control groups. The numbers of women with ≥1 hospital observation lasting <24 hours were not different between the groups. Compliance with monitoring did not significantly differ for women who were delivered at <35 weeks’ gestation, women with ≥2 cm cervical dilatation at enrollment, or for African American women. Conclusion: A reduction in the likelihood of preterm delivery at <35 weeks’ gestation was not further enhanced by the addition of home uterine monitoring to the outpatient management regimens of women treated for preterm labor. (Am J Obstet Gynecol 1999;180:798-805.)