Early Versus Delayed Oxytocin Augmentation in Nulliparous Women with Spontaneous Dysfunctional Labour: A Systematic Review and Meta-Analysis

Background: The timing of oxytocin for slow labour progress rests on custom rather than evidence, and existing syntheses pool clinically distinct populations. Objectives: We restricted this systematic review to nulliparous women in established active-phase labour with a trial-specified diagnosis of slow progress, comparing early versus delayed or withheld intravenous oxytocin. Methods: Cochrane review CD007123 was updated by searching MEDLINE, Embase and CENTRAL; counts were recomputed from primary reports. Results: Three trials (1102 women) were eligible. Early oxytocin did not alter caesarean delivery (three trials, 1102 women; risk ratio [RR] 0.86, 95% confidence interval [CI] 0.63–1.16), an interval excluding neither benefit nor harm. Uterine hyperstimulation, defined differently in the two contributing trials, was more frequent with early oxytocin (two trials, 472 women; RR 2.51, 95% CI 1.04–6.06), but 92% of the weight came from one trial and the association did not survive Hartung–Knapp or leave-one-out analysis. No difference was demonstrated for instrumental or spontaneous delivery, Apgar < 7, neonatal admission or haemorrhage. Labour was shorter by two hours (two trials, 1042 women; mean difference −2.17 h, 95% CI −3.54 to −0.80), with substantial heterogeneity. Certainty was low or very low. Conclusions: Early oxytocin may shorten labour; its effects on caesarean delivery and other outcomes remain uncertain.