Effectiveness and Clinical Efficacy of Hyoscine Butylbromide in Shortening the Active Phase of Labor Among Primagravidas: A Systematic Review and Meta‐Analysis

Aim Hyoscine butylbromide (HBB) is an anticholinergic antispasmodic used in some obstetric settings to facilitate cervical dilatation and shorten labor. In this systematic review, we sought to evaluate the effectiveness and clinical efficacy of HBB in shortening the active phase of labor among primigravid women. We also aimed to assess its impact on labor duration, cervical dilatation, mode of delivery, and maternal and neonatal outcomes. Methods Following PRISMA guidelines, we systematically searched PubMed, SCOPUS, Web of Science, and Lens.org for randomized controlled trials (RCTs) from January 2010 to May 2025. Included studies reported HBB's effect on labor outcomes in primigravidas in hospital settings. Data were pooled using a random‐effects model in Jamovi v2.6.44 (MAJOR module). Heterogeneity was assessed with I 2 , Tau 2 , and Cochran's Q statistics, and publication bias was evaluated using Egger's regression, Begg's test, and funnel plots. Results Seven RCTs from Egypt, Iran, Mexico, and India were included. HBB significantly reduced active labor duration (SMD = −1.67, 95% CI: −1.95 to −1.39, p < 0.001), corresponding to a 44–154 min reduction (mean 95.2 min). Moderate heterogeneity was observed ( I 2 = 65.46%, p = 0.005). No significant publication bias was detected (Egger's p = 0.521). HBB showed no consistent effect on mode of delivery or neonatal outcomes. Conclusion In trials conducted predominantly in low‐income settings, HBB was associated with a statistically significant and large reduction in active labor duration in primigravidas, without consistent effects on mode of delivery or neonatal outcomes. Because key co‐interventions (epidural/neuraxial analgesia and oxytocin augmentation) were not reported uniformly across trials, the findings should be interpreted cautiously and not generalized beyond low‐income contexts. Further adequately powered, blinded RCTs that explicitly account for co‐interventions and report patient‐important outcomes are needed before HBB can be recommended as a routine component of labor management.