Effect of menstrual cups on vaginal health, reproductive tract and urogenital infections: a systematic review and meta-analysis

Background
The menstrual cup is a device inserted into the vagina during menstruation to collect blood. Evidence of its effect on the vaginal microbiome and associations with laboratory-confirmed infections is limited. We compiled existing information to assess associations between menstrual cups and reproductive tract infections (RTIs), sexually transmitted infections (STIs), and the vaginal microbiome.

Methods
We searched four databases (PubMed, CINAHL, Global Health, and Scopus, from inception to January 23, 2026) for trials or observational studies reporting on menstrual cup use and laboratory-confirmed RTIs, STIs and the vaginal microbiome. Study quality was assessed using the Cochrane Collaboration tool for trials and the Joanna Briggs Institute Critical Appraisal Checklist for Cohort Studies. Outcomes of interest between cup-users and users of alternative menstrual products (non-cup users) were compared using prevalence ratios (PR). Meta-analyses were conducted using fixed-effects models to generate pooled estimates. PROSPERO registration: CRD42024559595.

Findings
Eleven studies involving 10,268 participants were included. Only three studies were considered of good quality. In two randomised controlled studies in Kenya, menstrual cups reduced the risk of STIs relative to non-cup users (adjusted PR [aPR] 0.74, 95% CI 0.60–0.91, p = 0.037, n = 695, I2 = 0.0%). The association with bacterial vaginosis was 0.81 (aPR, 0.63–1.04, p = 0.0963, n = 695, I2 = 0.0%). When combining observational and randomised studies, a protective effect on bacterial vaginosis persisted (PR 0.79, 95% CI 0.69–0.90, p = 0.0004, five studies, n = 2103, I2 = 0.0%, 3 continents). One trial showed an association between menstrual cups and HSV-2 of 0.71 (aPR, 95% CI 0.50–1.01, p = 0.057, n = 1451). Optimal vaginal community state type-1 (CST-I) was more likely among cup users compared to non-cup users (PR 1.18, 1.10–1.27, p < 0.0001, n = 2639, 5 studies in Kenya and Europe). No increased infection risks were noted among menstrual cup users across the infections evaluated. Main limitations included the low number and quality of existing studies.

Interpretation
Menstrual cups reduced the risk of STIs in Kenya. For bacterial vaginosis, the association was consistent with a protective effect and supportive for a healthy vaginal microbiome composition in studies from different geographies. These data strengthen evidence on the value of menstrual cups as a global multipurpose menstrual product solution.