Stem-cell therapy in stress urinary incontinence: A review.

The incidence of urinary incontinence (UI) is approximately 10%-40% in women, affecting one to two hundred million women worldwide. Stress UI (SUI) is characterized by involuntary urination due to increased abdominal stress and urine leakage without bladder contraction. Surgical treatments include midurethral slings, bulking agents, and Burch colposuspension to restore urethral continence. Nevertheless, an optimal treatment for all types of incontinence has not yet been established. Stem-cell therapy has emerged as a novel treatment for many diseases. Stem cells can self-renew and can differentiate into other cell types. Adult stem cells are suitable for clinical applications because they can be easily obtained noninvasively or minimal invasively. Stem-cell therapy for SUI has been studied preclinically and clinically. Muscle-derived progenitors have been used to treat SUI by promoting the regeneration of rhabdomyosphincters. The human trial used transurethral injection of autologous muscle-derived stem cells to improve sphincter contractility and function. Other sources of stem cells have also been studied in SUI treatment, such as umbilical cord blood, amniotic fluid, bone marrow, urine, and adipose tissue. The success rate of stem-cell therapy for SUI ranges from 13% to 100%. This review aimed to summarize the current status of stem-cell treatments for SUI, with respect to clinical trials, cell types, transplantation routes, and dosage volume and frequency.