Stress Urinary Incontinence and Urethral Hypermobility
A 50-year-old woman, para 5, reports 2 years of urine leakage occurring only when she coughs, sneezes, or lifts her grandchildren. She denies urgency, frequency, nocturia, or dysuria. Urinalysis is negative and post-void residual volume is 20 mL. Which of the following is the most likely finding on her pelvic examination?
- A.Urethral hypermobility on Q-tip testingCorrect
- B.Posterior vaginal wall rectocele
- C.Enterocele bulging at the vaginal apex
- D.Lateral paravaginal support defect
Explanation
Leakage triggered exclusively by coughing, sneezing or lifting, without urgency or irritative symptoms, defines stress urinary incontinence. The underlying anatomic lesion in most multiparous women is loss of the pelvic floor and endopelvic fascial support of the bladder neck and proximal urethra, so that with a rise in intra-abdominal pressure the urethra rotates downward and out of the abdominal pressure zone. Pressure is then transmitted to the bladder but not equally to the urethra, bladder pressure transiently exceeds urethral closing pressure, and urine escapes. This descent is urethral hypermobility, demonstrated at the bedside by the Q-tip test: a lubricated cotton swab placed in the urethra to the bladder neck deflects more than 30 degrees from horizontal on Valsalva. Vaginal delivery, high parity, obesity, chronic cough and aging are the principal risk factors. A rectocele produces obstructed defecation and splinting, not incontinence. An enterocele presents as an apical vaginal bulge and pressure. A paravaginal defect causes lateral anterior wall prolapse and may coexist with stress incontinence, but the direct examination correlate of the leakage itself is urethral hypermobility. First-line treatment is pelvic floor muscle training, with a midurethral sling if conservative therapy fails.
Why each option
- A.
- Correct. Loss of bladder neck support allows the urethra to rotate downward with straining; a Q-tip deflection greater than 30 degrees confirms hypermobility.
- B.
- A rectocele causes constipation and the need to splint the posterior vaginal wall to defecate, not stress leakage.
- C.
- An enterocele is small bowel herniating into the vaginal apex and presents as a bulge and pelvic pressure.
- D.
- A paravaginal defect produces lateral anterior wall descent; it may accompany stress incontinence but is not the finding that explains the leakage.
Reference: Williams Gynecology, 4th ed., 2020; ACOG Practice Bulletin 155, Urinary Incontinence in Women
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