Background: Caesarean section rates are over 20% in many developed countries. The main diagnosis contributing to the high rate in nulliparae is dystocia or prolonged labour. The present review assesses the effects of a policy of early amniotomy with early oxytocin administration for the prevention of, or the therapy for, delay in labour progress.
Objectives: To estimate the effects of early augmentation with amniotomy and oxytocin for prevention of, or therapy for, delay in labour progress on the caesarean birth rate and on indicators of maternal and neonatal morbidity.
Search strategy: We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (November 2008), MEDLINE (January 1970 to November 2008), EMBASE (1980 to November 2008), CINAHL (1982 to November 2008), MIDIRS (1985 to November 2008) and contacted authors for data from unpublished trials.
Selection criteria: Randomized and quasi-randomized controlled trials that compared oxytocin and amniotomy to expectant management.
Data collection and analysis: Three authors extracted data independently. We stratified the analyses into 'Prevention Trials' and 'Therapy Trials' according to the status of the woman at the time of randomization. Participants in the 'Prevention Trials' were unselected women, without slow progress in labour, who were randomized to a policy of early augmentation or to routine care. In 'Treatment Trials' women were eligible if they had an established delay in labour progress.
Main results: Twelve trials, including 7792 women, were included. The unstratified analysis found early intervention with amniotomy and oxytocin to be associated with a modest reduction in the risk of caesarean section; however, the confidence interval crossed unity and was compatible with no effect (risk ratio (RR) 0.89; 95% confidence interval (CI) 0.79 to 1.01). In Prevention trials, early augmentation was associated with a modest reduction in the number of caesarean births (RR 0.88; 95% CI 0.77 to 0.99). A policy of early amniotomy and early oxytocin was associated with a shortened duration of labour (mean difference - 1.11 hour). Sensitivity analyses excluding three trials with a full package of Active Management did not substantially affect the point estimate of the effect (RR 0.87; 95% CI 0.73 to 1.04). We found no other significant effects for the other indicators of maternal or neonatal morbidity.
Authors' conclusions: In prevention trials, early intervention with amniotomy and oxytocin appears to be associated with a modest reduction in the rate of caesarean section over standard care.