Urinary incontinence

Urinary incontinence is the involuntary loss of urine. Several types are grouped under that single name, and they look alike from the outside but arise for very different reasons, which is why it helps to keep them apart.

In stress incontinence, leakage happens the moment pressure inside the abdomen rises: with a cough, a sneeze, a heavy lift. What fails there is the seal, from weakness of the urethral sphincter, the muscle that closes the outlet, or of the pelvic floor that supports it. In urge incontinence the problem lies elsewhere: the detrusor, the muscle in the bladder wall, contracts on its own. In one, the seal fails when pressure rises; in the other, the bladder contracts without permission.

And there is a third type in which neither the bladder nor the sphincter is at fault. In functional incontinence, urine is lost because environmental or physical barriers stand in the way of reaching the toilet in time.