Influence of pelvic floor muscle fatigue on stress urinary incontinence: a systematic review

Introduction and hypothesis Stress urinary incontinence (SUI) is the most common urinary complaint among women and is defined by the International Continence Society as any involuntary loss of urine due to physical effort, sneezing or coughing. Many women with SUI state that the loss of urine occurs after performing repetitive movements, which may suggest that it is the result of fatigue of the pelvic floor muscles (PFM). Thus, we performed the systematic review of the literature on the influence of PFM fatigue on the development or worsening of the symptoms of SUI in women. Methods The PubMed, Scopus, EMBASE, PEDro, LILACS, SciELO, Cochrane Library, Google Scholar, CINAHL and Periodicos CAPES databases were searched for articles using the keywords fatigue, pelvic floor, stress urinary incontinence and women, in Portuguese and in English. Methodological quality was assessed using the Downs and Black scale, and the data collected from the studies were analyzed descriptively. Results Of the 2,010 articles found, five met the inclusion criteria and were analyzed. They were published between 2004 and 2015, and included a total of 30,320 women with ages ranging from 24 to 53.6 years. Of the studies analyzed, three showed an association between fatigue and SUI, and two did not show such an association. Conclusions This study confirmed that PFM fatigue can influence the development and/or worsening of SUI.