Urinary incontinence: The unintentional loss of urine. Inability to hold urine in the bladder due to loss of voluntary control over the urinary sphincters resulting in the involuntary passage of urine.
One cause of urinary incontinence is an overactive bladder. There is a sudden involuntary contraction of the muscular wall of the bladder resulting in urinary urgency, an immediate unstoppable need to urinate.
