Urethral pressure increment preceding and following bladder pressure elevation during stress episode in healthy and stress incontinent women

The urethral pressure elevation preceding and following pressure elevation in the bladder during cough was studied in 30 healthy volunteers and 30 genuine stress‐incontinent women. The pressures were measured by means of a double microtip transducer catheter with the distal sensor in the bladder and the proximal sensor covered with a water‐filled balloon and placed at the bladder neck, in the high‐pressure zone, or distally in the urethra. In both groups of women a urethral pressure elevation was demonstrated before and after pressure elevation in the bladder during a cough. A urethral pressure elevation ≥ 5 cm H 2 O both before and after bladder pressure elevation was demonstrated in one third and one fourth of healthy and stress‐incontinent women, respectively. The initial urethral pressure rise in the mid‐ and distal urethra was statistically significantly higher in the healthy women. During abrupt coughing the initial urethral pressure rise disappeared. The pelvic floor as part of the demarcation of the abdominal cavity is positively taking part in the intraabdominal pressure generation during stress episodes, and the urethral pressure increment in advance of bladder pressure elevation reflects an active contraction. A lowering of this initial urethral pressure rise may be a contributing factor of the pathogenesis of genuine stress incontinence, although it does not necessarily result in stress incontinence.