Clinical and urodynamic assessment of nulliparous young women with and without stress incontinence symptoms: a case-control study.

OBJECTIVE: To assess the prevalence of stress urinary incontinence symptoms in young, nulliparous, physically fit women, evaluate their clinical and urodynamic characteristic, and compare them to a matched asymptomatic control group.
METHODS: All first-year physical education students (N = 37) were asked to participate in a four-step study on urinary incontinence. The study included an interview, a clinical examination (incorporating an assessment of pelvic floor muscle strength), ambulatory urodynamics during exercise, and a needle electromyographic assessment of pelvic floor muscles and the striated urethral wall muscle with simultaneous urethral and bladder-pressure measurements.
RESULTS: Thirteen (38%) subjects reported stress urinary incontinence symptoms. Eight of the 13 reported the condition to be a social or hygienic problem; six experienced leakage more than once a week. The mean quantity of leakage of the symptomatic women during ambulatory urodynamics was 12 g (range 0-43). No uninhibited detrusor contractions were detected during leakage episodes. Six of seven subjects with symptoms were found to have urodynamic evidence of urethral sphincteric incompetence. There were no differences between the symptomatic and the control group in body mass index, percent body fat, pelvic floor muscle strength, menstrual cycle, and electromyographic patterns. Four of seven women in the symptomatic group had benign hypermobility joint syndrome, whereas there were none in the control group.
CONCLUSION: Physically fit nulliparous women have a high prevalence of stress incontinence symptoms and evidence of urethral sphincteric incompetence.