The effect of Hyoscine N-butyl bromide (HBB) rectal on the duration of labor and rate of cervical dilatation: A systematic review and meta-analysis.

OBJECTIVE: The current meta-analysis was designed to investigate the impact of Hyoscine N-butyl bromide (HBB) rectal on labor duration and the rate of cervical dilatation by consolidating the available data.

METHODS: The search of MEDLINE through the PubMed interface, Scopus, ScienceDirect, and the Cochrane Central Register of Controlled Trials (CENTRAL) was performed for original articles concerning the effects of HBB rectal on the duration of labor published prior to 26 June 2023. Search terms were based on MESH without time and language restrictions. They included: Hyoscine, Scopolamine, HBB, Buscopan, Buscolysin, Buscapine, rectal, suppository, childbirth, delivery, active phase, second stage, cervical dilatation, labor, labour, and duration of labor. The Comprehensive Meta-Analysis V3 software (CMA software) was used for all analyses.

RESULTS: Five randomized control trials and one non-randomized study involving 1310 women were included in the systematic review. Two studies were excluded from the meta-analysis because of heterogeneous interventions and a lack of mean and standard deviation results. The results determined that HBB rectal administration significantly decreased the duration of the active phase (pooled mean difference -193.893; 95% confidence interval -229.173, -158.613; P < 0.001; I2 squares = 90.097%) and second stage of labor (pooled mean difference -2.911; 95% confidence interval -5.486, -0.336; P = 0.027; I2 squares = 90.097%). Also, the cervical dilatation rate in the active phase of labor was 0.981 cm/h higher than in the control group (I2 = 0.0%; P < 0.001).

CONCLUSION: This meta-analysis found that HBB rectal administration shortened the active labor phase and second stage and increased the rate of cervix dilatation; consequently, it can be used as a cost-effective intervention for low-risk pregnant women during labor. Although, our findings also suggest that more robust clinical trials are required to generate evidence and confirm the use of HBB during labor for clinical practice guidelines.