The Efficacy of Oxytocin Gel in Postmenopausal Women with Vaginal Atrophy: An Updated Systematic Review and Meta-Analysis

Abstract Background Genitourinary syndrome of menopause (GSM) is a common disturbing issue in the postmenopausal period. Unlike vasomotor symptoms, it has a progressive trend. Our study aims to evaluate the efficacy and safety of oxytocin gel versus placebo gel in postmenopausal women with GSM. Methods A systematic review and meta-analysis synthesizing randomized controlled trials (RCTs) from Web of Science, SCOPUS, PubMed, and Cochrane Central Register of Controlled Trials databases on January 18, 2023. We used the risk ratio (RR) for dichotomous outcomes and mean difference (MD) for continuous outcomes; both presented with the corresponding 95% confidence interval (CI). Results Seven studies with 631 patients were included. Regarding the maturation index, there was a statistically insignificant increase in the oxytocin arm (MD= 12.34, 95% CI (-12.52-37.19), P= 0.33). Vaginal atrophy showed a statistically significant reduction in the oxytocin group (RR= 0.32, 95% CI (0.23-0.10), P< 0.00001). For dyspareunia, vaginal pH as well as histological evaluation of vaginal atrophy, there was a statistically insignificant difference between the two groups (RR= 1.02, 95% CI (0.82 -1.27), P= 0.84), (MD= -0.74, 95% CI (-1.58-0.10), P= 0.08) and (MD= -0.38, 95% CI (-0.82-0.06), P= 0.09) respectively. There was no significant difference in the safety profile between the two groups as measured by endometrial thickness (MD= 0.00, 95% CI (-0.23-0.23), P= 0.99). Conclusions Although oxytocin has been proposed as a viable alternative to estrogen in the treatment of GSM, our findings show the opposite. Larger, high-quality RCTs are needed to confirm or refute our results. PROSPERO number CRD42022334357.