Hydrogel-Based Therapies for Female Stress Urinary Incontinence: From Bulking Agents to Regenerative Platforms-A...

This review summarizes the procedural techniques, short- and long-term efficacy, and clinical application of polyacrylamide hydrogel (PAHG, Bulkamid®) as a urethral bulking agent for female stress urinary incontinence (SUI); compares PAHG with mid-urethral sling (MUS) surgery; and examines emerging hydrogel-based regenerative platforms, used for mechanical bulking, delivery of bioactive molecules or cells, and extracellular matrix-mimetic scaffolding, together with their prospects for clinical translation.

PAHG injection has gained acceptance as a minimally invasive option for patients who have failed conservative management, declined or are intolerant of MUS surgery, or have recurrent SUI. Follow-up studies up to 7-9 years show sustained response rates of 44%-65% with mostly transient complications and improvements in quality of life and sexual function. Randomized trials indicate that although MUS achieves superior cure rates, PAHG is associated with fewer severe complications, aligning with patient preferences for less invasive procedures. In preclinical animal models, injectable hydrogels loaded with bioactive molecules or cells provide mechanical bulking and simultaneously promote tissue regeneration, including angiogenesis, neurogenesis, and modulation of the inflammatory response. PAHG is a well-tolerated, minimally invasive bulking agent that achieves sustained symptomatic relief and meaningful quality-of-life improvements. Dual-function hydrogel systems combining bulking and sustained regenerative repair may represent a future direction for SUI therapy; however, most evidence remains preclinical, and further material optimization, rigorous safety evaluation, and well-designed clinical trials are needed before clinical translation.