A multicenter randomized controlled trial of home uterine monitoring: active versus sham device. The Collaborative Home Uterine Monitoring Study (CHUMS) Group.

OBJECTIVE: Our purpose was to determine the efficacy of a home uterine activity monitoring system for early detection of preterm labor and reduction of preterm birth.

STUDY DESIGN: A randomized, controlled, double-blinded trial was performed in which pregnant women between 24 and 36 weeks' gestation and at high risk for preterm labor or birth were assigned to receive twice daily nursing contact and home uterine activity monitoring with either active (data revealed) or sham (data concealed) devices. Study end points included mean cervical dilatation and its mean change from a previous visit at preterm labor diagnosis, preterm birth rate, and infant outcomes. Analysis of variance or logistic models including terms for site and group-by-site interaction effects were constructed for all variables.

RESULTS: Of 1355 patients enrolled, 1292 were randomized, 1165 used home uterine activity monitoring devices, and 842 (72.3%) completed the study. Both device groups had similar demographics, enrollment and delivery gestational ages, discontinuation rates, risk factors, birth weights, cervical dilatation at enrollment and at preterm labor diagnosis, change in cervical dilatation at preterm labor diagnosis, rates of preterm labor and birth, and neonatal intensive care requirements. Power to detect a difference in cervical dilatation > or = 1 cm at diagnosis of preterm labor was 0.99 for all risk factors.

CONCLUSIONS: Uterine activity data obtained from home uterine activity monitoring, when added to daily nursing contact, were not linked to earlier diagnosis of preterm labor or lower rates of preterm birth or neonatal morbidity in pregnancies at high risk for preterm labor and birth.