Antenatal interventions to reduce preterm birth: an overview of Cochrane systematic reviews
BACKGROUND To reduce the morbidity and mortality associated with preterm birth, home uterine activity monitoring aims for early detection of increased contraction frequency, and early intervention with tocolytic drugs to inhibit labour and prolong pregnancy. However, the effectiveness of such monitoring is disputed. OBJECTIVES To determine whether home uterine activity monitoring is effective in improving the outcomes for women and their infants considered to be at high risk of preterm birth, when compared with conventional or other care packages that do not include home uterine monitoring. SEARCH METHODS We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (30 November 2011), CENTRAL (The Cochrane Library 2011, Issue 4 of 4), MEDLINE (1966 to 30 November 2011), EMBASE (1974 to 30 November 2011), CINAHL (1982 to 30 November 2011) and scanned reference lists of retrieved studies. SELECTION CRITERIA Randomised control trials of home uterine activity monitoring, with or without patient education programmes, for women at risk for preterm birth, in comparison to the same care package without home uterine activity monitoring. DATA COLLECTION AND ANALYSIS Two review authors independently assessed trials for inclusion, extracted data and assessed risk of bias. Data were checked for accuracy. We did not attempt to contact authors to resolve queries. MAIN RESULTS There were 15 included studies (total number of enrolled participants 6008); 13 studies contributed data. Women using home uterine monitoring were less likely to experience preterm birth at less than 34 weeks (risk ratio (RR) 0.78; 95% confidence interval (CI) 0.62 to 0.99; three studies, n = 1596; fixed-effect analysis). However, this significant difference was not evident when we carried out a sensitivity analysis, restricting the analysis to studies at low risk of bias based on study quality (RR 0.75; 95% CI 0.57 to 1.00, one study, 1292 women). There was no significant difference in the rate of perinatal mortality (RR 1.22; 95% CI 0.86 to 1.72; two studies, n = 2589).There was no significant difference in the number of preterm births at less than 37 weeks (average RR 0.85; CI 0.72 to 1.01; eight studies, n = 4834; random effects, T(2) = 0.03, I(2) = 68%). Infants born to women using home uterine monitoring were less likely to be admitted to neonatal intensive care unit (average RR 0.77; 95% CI 0.62 to 0.96; five studies, n = 2367; random-effects, T(2) = 0.02, I(2) = 32%). Although this difference was not statistically significant when only high quality studies were included (RR 0.86; 95% CI 0.74 to 1.01; one study, n = 1292). Women using home uterine monitoring made more unscheduled antenatal visits (mean difference (MD) 0.49; 95% CI 0.39 to 0.62; two studies, n = 2807). Women using home uterine monitoring were also more likely to have prophylactic tocolytic drug therapy (average RR 1.21; 95% CI 1.01 to 1.45; seven studies, n = 4316; random-effects. T(2) = 0.03, I(2) = 62%) but this difference was no longer significant when the analysis was restricted to high quality studies (average RR 1.22; 95% CI 0.90 to 1.65, three studies, n = 3749,random effects, T(2) = 0.05, I(2) = 76%). One small study reported that the home uterine monitoring group spent fewer days in hospital antenatally. No data on maternal anxiety or acceptability were found. AUTHORS' CONCLUSIONS Home uterine monitoring may result in fewer admissions to a neonatal intensive care unit but more unscheduled antenatal visits and tocolytic treatment. There is no impact on maternal and perinatal outcomes such as perinatal mortality or incidence of preterm birth.