The causes of the most common types of urinary incontinence are:
Stress incontinence. Stress incontinence camera is caused by stretched pelvic floor muscles, as from childbirth or weight gain. When these muscles no longer support your bladder properly, the bladder drops downward and pushes against the vagina, preventing tightening of the muscles that ordinarily close off the urethra. Leakage can then occur when extra pressure is exerted with coughing, sneezing, laughing, or other activities. A chronic cough from smoking can also make stress incontinence worse.
Urge incontinence. Urge incontinence results when the bladder muscle involuntarily contracts. This causes a very strong urge to urinate. You leak urine if you can't get to the toilet in time.
Overactive bladder is a kind of urge incontinence. But not everyone with overactive bladder leaks urine. For more information, see the topic Overactive Bladder.
It is common for a woman to have mixed incontinence, usually a combination of stress incontinence and urge incontinence.
Less common types of urinary incontinence have other causes. These types include:
Polyuria (excessive urine production) of which, in turn, the most frequent causes are: uncontrolled diabetes mellitus, primary polydipsia (excessive fluid drinking), central diabetes insipidus and nephrogenic diabetes insipidus. Polyuria generally causes urinary urgency and frequency, but doesn't necessarily lead to incontinence.
Caffeine or cola beverages also stimulate the bladder.
Enlarged prostate is the most common cause of incontinence in men after the age of 40; sometimes prostate cancer may also be associated with urinary incontinence. Moreover drugs or radiation used to treat prostate cancer can also cause incontinence.
Disorders like multiple sclerosis, spina bifida, Parkinson's disease, strokes and spinal cord injury can all interfere with nerve function of the bladder.