Sexual Function After Obstetric Anal Sphincter Injuries (OASIs): A Systematic Review and Meta-Analysis

Abstract Background Obstetric anal sphincter injuries (OASIs) may lead to life changing sequelae. Objective The aim was to determine whether sustaining an OASI independently influences postpartum sexual function. Search Strategy MEDLINE, Embase and the Cochrane Library were searched (inception to 12 July 2024) for eligible studies comparing women who had undergone vaginal delivery with and without OASI. Two reviewers screened, extracted data and assessed risk of bias with JBI/CASP checklists. Pooled effects were calculated with DerSimonian-Laird random-effects models; heterogeneity was explored with I 2 . Results Twenty-two studies met inclusion criteria; no meta-analysis pooled more than six studies, yielding low-certainty evidence. Exploratory pooled estimates suggested women with an OASI were 30% less likely to be sexually active at 3 months postpartum [RR 0.69 (95% CI 0.49-0.95), p = 0.03] and more likely to suffer from dyspareunia at 3 months [RR 1.58 (95% CI 1.14-2.17), p = 0.005] and > 12 months postpartum [RR 1.69 (95% CI 1.31-2.17), p < 0.001] when compared to the control group. FSFI outcomes were sparsely reported and largely derived from single studies; limited data suggested lower domain scores at 2 and 12 months among women with OASI. Conclusion Available evidence is observational, heterogeneous and frequently lacks baseline sexual function assessment, substantially limiting causal inference. Quantitative findings should therefore be interpreted as exploratory. High-quality, baseline-controlled prospective studies using standardised outcome measures are needed. In the interim, proactive enquiry during the postnatal follow-up of OASI patients represents a low-risk, patient-centred approach to addressing under-reported sexual health concerns.