Pathophysiology of urinary incontinence and pelvic organ prolapse.

Stress urinary incontinence is the complaint of involuntary leakage of urine on effort or exertion, or on sneezing or coughing. In urodynamic terms, stress continence is maintained when the maximum urethral pressure exceeds the intravesical pressure. In the McGuire classification system, type 1 and 2 stress incontinence occur because of urethral hypermobility and type 3 because of intrinsic sphincter deficiency (ISD). More recently it has been suggested that there is a spectrum of urethral characteristics in women with stress urinary incontinence and ‘delineation into categories may be simplistic and arbitrary and requires further research’.