Circumvaginal surface electromyography in women with urinary incontinence and in healthy volunteers.

In this study we developed a probe for surface EMG investigation of the circumvaginal muscle function in women with various forms of urinary incontinence. 69 women were investigated, 20 healthy volunteers, 25 patients with stress incontinence, 11 with urge incontinence and 13 with a mixed type of incontinence. We found that the circumvaginal surface EMG activity at short lasting (2 sec) maximum contraction was significant lower in patients with incontinence compared to healthy volunteers. We also found that the ability to hold a maximum contraction during one minute was significant reduced in all the patient groups compared to controls. The results suggest that patients with stress, urge or mixed incontinence all seem to have a defective function of the circumvaginal musculature. A common aetiology for stress, urge and mixed incontinence seems to be a reasonable working hypothesis for future investigations.