Controlling the bladder neck position is key to continence

Stress urinary incontinence (SUI) is a problem of varying degrees for many women who’ve had babies. The pelvic floor muscles (PFMs) actively contribute to keeping us continent yet other factors also contribute to staying dry when active. Defects in the urethral sphincters, in the connective tissues and the nerve supply all play a role in continence.

When the continence mechanism is challenged (coughing, sneezing, running) the rise in intra-abdominal pressure enhances closure only if the urethra remains in position between the anterior vaginal wall and the pelvic floor. Women with SUI have a larger urethral travel (hyper mobile) during coughing than continent women. This suggests women with SUI lack effective support from the endopelvic fascia and /or PFMs are slow or ineffective in giving support to the urethra.

A study by McLean titled ‘Pelvic floor muscle training in women with stress incontinence causes hypertrophy of urethral sphincters and reduces bladder neck mobility in coughing’1 concluded, ‘Physiotherapist-supervised PFM training reduces bladder neck motion during coughing and results in hypertrophy of the urethral sphincter in women who present with SUI’.

The women in the treatment group demonstrated significant improvements in the 3-day bladder diary and Incontinence Impact Questionnaire after the PFM training and improved significantly more than the control group.

Results: The women in the treatment group showed reduced bladder neck mobility during coughing and increased cross sectional area of their urethra after as compared to before the training. These changes were not evident in the control group. No differences in the resting position of the bladder neck or in bladder neck excursion during Valsalva maneuver were noted in either group. Forty women with SUI were randomly assigned to two groups: the treatment group received 12 weekly physiotherapy session during which they learned to effectively contract their PFMs, and a home exercise program was prescribed, reviewed and progressed. The control group received no treatment. Before and after the 12-week study period, ultrasound imaging was used to evaluate bladder neck position and mobility during coughing and Valsalva maneuver in lying and standing, along with urethral morphology.

Secondary outcome measures included a 3-day bladder diary, 30-minute pad test and the Incontinence Impact Questionnaire and the Urogenital Distress Inventory.

The authors conclude that PFM training results in urethral sphincter hypertrophy. This is of particular clinical relevance as it suggests a mechanism through which PFM training may be effective in treating SUI in women who do not have intact PFMs or in whom the PFMs are already strong but the urethral sphincters are damaged or weak.


  1. Pelvic floor muscle training in women with stress incontinence causes hypertrophy of urethral sphincters and reduces bladder neck mobility in coughing. Linda McLean, Kevin Varette, Evelyne Gentilcore-Saulnier, Marie-Andree Harvey, Kevin Baker, Eric SauerbreiNeurourol. Urodynam. 32:1096-1102, 2013.