Effects of Algorithm for Diagnosis of Active Labor : Cluster Randomized Trial

Over 30% of women admitted to labor wards may not be in active labor, and once admitted, receive oxytocin and other labor interventions more frequently than those admitted in active labor. A previous randomized controlled trial reported that adhering to strict criteria for diagnosis of labor reduced the use of oxytocin and other interventions in such patients; the study was small and there was no confirmatory data from other controlled trials. The investigators hypothesized that use of an algorithm with strict diagnostic criteria would reduce the need for oxytocin and other labor interventions in primiparous women compared with standard care. This cluster randomized trial compared the maternal and neonatal outcomes in 4503 primiparous women managed either according to an algorithm with strict criteria for the diagnosis of active labor or according to standard care at 14 maternity units in Scotland. Following randomization, women in the interventional group received care according to the algorithm, whereas women in the control group received normal care. For the algorithm group, a baseline sample of 1029 women and a postimplementation sample of 896 women were collected from 7 experimental clusters. For the control group, a baseline sample of 1291 women and a postimplementation sample of 1287 women were obtained from 7 control clusters. Clinical data were analyzed for 892 women in the algorithm group and 1279 women in the control group. The primary study outcome was the use of oxytocin for augmentation of labor. The data showed that the proportion of women given oxytocin for augmentation of labor was not significantly different between the algorithm and control groups (difference: 0.3%; 95% confidence interval [CI]: -9.2-9.8, P = 0.9). There was also no difference between the 2 groups in the use of other medical interventions. Compared to the control group, significantly more women in the algorithm group were likely to be discharged home after their first admission (difference: -19.2%; 95% CI: -29.9 to -8.6, P = 0.002) and to have several admissions and discharges before admission leading to delivery (difference: 0.29; 95% CI: 0.04-0.55, P = 0.03). These findings suggest that adherence to an algorithm with strict criteria for diagnosis of active labor in women with spontaneous labor does not reduce the use of oxytocin or other medical interventions.