Please note: In 2003, the CTF updated its Grades of Recommendations to include an "I Recommendation" for situations where insufficient evidence exists to allow a recommendation to be made.  (Formerly, these situations were captured under a "C Recommendation".)  This change is not retroactive, and all "C Recommendations" made prior to 2003 have not been reevaluated in light of the new "I" recommendation grade.  For a discussion of these recommendation grades, please link to the 2003 article in the Canadian Medical Association Journal here.

The Use of Home Uterine Activity Monitoring to Prevent Preterm Birth

Adapted by Geoffrey Anderson, MD, PhD, Institute for Clinical Evaluative Sciences and Department of Health Administration, University of Toronto, from the report  prepared for the US Preventive Services Task Force by Steven H. Woolf, MD, MPH

Objective
To make recommendations for the use of home uterine activity monitoring for preventing preterm birth in Canadian women.

Burden of Suffering
Birth before 36 or 37 weeks of gestation is defined as preterm birth.  The incidence of preterm birth is about 6 percent of total deliveries in Canada.  Such births account for 75-85% percent of perinatal mortality, and about 10-15% percent of survivors having major handicaps.

Options
Options include no monitoring and monitoring with a home uterine activity monitor with a tocodynamometer plus telephone data transfer and analysis. Telephone reassurance was also given. Prevention of preterm labour includes detection of labour (defined as consistent contractions with cervical change) at an early enough stage to allow for use of tocolytic drugs. Both normal pregnancy and high-risk pregnancies (previous preterm deliveries, multiple gestations, uterine anomalies, and other risk factors) were studied.

Outcomes
Neonatal mortality, gestational age at birth, birth weight, time spent in the hospital and neonatal intensive care unit, need for oxygen therapy and mechanical ventilation, development of respiratory distress syndrome, term delivery, hospitalization for preterm labour, and cervical changes. Equipment and monitoring costs were considered.

Evidence
These recommendations were adapted from a report prepared for the U.S. Preventive Services Task Force.  MEDLINE was searched up to1993 using the keywords monitoring, physiological; home care services; fetal monitoring, and home.

Values
The 13-member Task Force of experts in family medicine, geriatric medicine, pediatrics, psychiatry and epidemiology used an evidence-based method for evaluating the effectiveness of preventive health care interventions. Recommendations were not based on cost-effectiveness of options. Patient preferences were not discussed.

Background papers providing critical appraisal of the evidence and tentative recommendations prepared by the chapter author were pre-circulated to the members. Evidence for this topic was presented and deliberated upon in 1- to 2-day meetings from March 1993 to June 1993. Consensus was reached on final recommendations.

Benefits, Harms, and Costs
6 RCTs have studied women with high-risk pregnancies and none have studied low-risk pregnancies. The control group women generally received usual care (often telephone calls and education). The home uterine monitoring group received training in the use of the equipment and they monitored contractions for 1 hour 2 to 3 times per day. If 4 contractions per hour occurred, they monitored contractions again for an hour while lying down. Data were transmitted by telephone to tocographs and analyzed; telephone support was provided by a study nurse.

2 studies by the same group (total 309 patients) found no differences between the groups for incidence of preterm labour, preterm deliveries, gestational age at delivery, or mean birth weight. A French study of 94 high-risk women also found no differences in rate of hospital admission for threatened preterm labour, incidence of preterm births or birth weight< 2500 g. One study (251 women) in California found that most differences were in the subgroups of women with twins and with preterm labour before 43 weeks' gestation. One study of 69 women found an average of 4 weeks longer gestation in the monitoring group. Another study with a large number of women not included in the analysis found monitored babies weighed more, needed fewer days in the neonatal intensive care unit, and had less need for oxygen therapy or mechanical ventilation. All studies had design flaws or unequal control groups.

Cost was approximately $90/d Cdn for equipment and monitoring charges ($630 to $7560 per monitored pregnancy).

Recommendations
Recommendation grade [A, B, C, D, E]  and level of evidence [I, II-1, II-2, II-3, III] are indicated after each recommendation. Citations in support of individual recommendations are identified in the guideline text.

Validation
This report was externally peer reviewed. The 1989 U.S. Preventive Services Task Force recommended against use of home uterine activity monitors in low-risk pregnancies and found insufficient evidence of clinical effectiveness to recommend for or against home uterine activity monitors as a screening test in high-risk pregnancies. The British Columbia Office of Health Technology Assessment does not recommend use of home uterine activity monitoring even for high-risk pregnancies. The Society of Obstetricians and Gynecologists of Canada has not made an official recommendation on their use.

Sponsors
The Canadian Task Force on Preventive Health Care developed this guideline with funding from Health Canada.

Selected References

Source Document
Anderson G. The use of home uterine activity monitoring to prevent preterm birth. In: Canadian Task Force on the Periodic Health Examination. Canadian Guide to Clinical Preventive Health Care. Ottawa: Health Canada, 1994; 146-55.

Other
U.S. Preventive Services Task Force. Home uterine activity monitoring for preterm labor: Review article. JAMA. 1993;270:369-70.