Relationship between urethral and vaginal pressures during pelvic muscle contraction. The Continence Program for Women Research Group.

Condensation is the performance of an effective pelvic muscle contraction increases urethral and vaginal pressures and is independent of demographic, clinical, and urodynamic factors. Our objective was to examine the relationship between urethral closure pressure and vaginal pressure during a pelvic muscle contraction in minimally trained women. Our secondary aim was to determine whether demographic, clinical, or urodynamic factors predict pelvic muscle contraction performance. Two hundred two women with urinary incontinence underwent multichannel urodynamic evaluation, including urethral profilometry and measurement of vaginal pressure during pelvic muscle contraction. One hundred forty-four women were diagnosed with genuine stress incontinence, 28 with detrusor instability, and 30 with mixed incontinence. Urethral and vaginal pressures correlated significantly during pelvic muscle contraction (P < or = 0.006). The ability to perform an adequate pelvic muscle contraction was independent of subject age, parity, hormonal or hysterectomy status, clinical severity, urethral support, and urethral profilometry measures (P > or = 0.42).