Effectiveness and safety of polyacrylamide hydrogel injection for female stress urinary incontinence: A systematic review and single-arm meta-analysis

Introduction: Polyacrylamide hydrogel (PAHG) injection is a minimally invasive treatment option for female stress incontinence, but reported effectiveness and durability vary across studies. This study aims to evaluate the effectiveness, safety, and retreatment rates of PAHG injection for female SUI through a systematic review and meta-analysis. Methods: A systematic review and meta-analysis were conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 guidelines and registered in PROSPERO (CRD420261328968). Literature was retrieved from electronic databases, such as PubMed, ProQuest, EuroPMC, and EBSCO, from database inception through February 2026. Cohort studies assessing PAHG injection for SUI were systematically reviewed. Random-effects models were used, heterogeneity was assessed with I 2 , and meta-regression examined age and follow-up as moderators. Publication bias was evaluated using funnel plots and Egger’s test. Results: Thirteen studies, including 1797 patients, were analyzed. The pooled responder rate was 72% (95% confidence interval [CI] 64%–78%; I 2 = 87%). A greater mean age was significantly associated with higher response rates ( P = 0.04). Four studies reporting International Consultation on Incontinence Questionnaire outcomes demonstrated a pooled mean reduction of −6.65 points (95% CI: −8.52 to −4.78; I 2 = 92.8%). The pooled repeat injection rate was 16% (95% CI: 10%–27%; I 2 = 94%). Follow-up duration did not significantly influence retreatment rates ( P = 0.85). No evidence of publication bias was detected for the primary outcome ( P = 0.96). Conclusion: PAHG injection is a minimally invasive treatment associated with clinically meaningful symptom improvement and a favorable safety profile in women with SUI. However, given the single-arm design of the included studies and substantial heterogeneity, these findings should be interpreted with caution.