Causes - Urinary incontinence

Urinary incontinence is when the normal way of peeing and storing pee is disturbed. It can happen for many reasons. But certain things can increase your chance of developing urinary incontinence.

Some of the causes lead to short-term urinary incontinence. Others may cause a long-term problem. If the cause can be treated, this may cure your incontinence.

Causes of stress incontinence

Stress incontinence happens when your bladder fills with pee. The pressure put on your bladder is greater than the strength your urethra needs to stay closed. The urethra is the tube through which pee passes out from your body.

Any sudden extra pressure put on your bladder, such as laughing, can cause pee to leak out of your urethra.

Your urethra may not be able to stay closed if the muscles in your pelvis are weak or damaged. It may also be unable to stay closed if your urethral sphincter is damaged.

These problems may be caused by:

• damage during childbirth, particularly if the child was born vaginally
• increased pressure on your tummy, for example, because you are pregnant or obese
• damage to the bladder or nearby area during surgery
• neurological conditions that affect the brain and spinal cord, for example Parkinson's disease
• some connective tissue disorders, such as Ehlers-Danlos syndrome
• some medicines

Causes of urge incontinence

The urgent and frequent need to pee can be caused by a problem with the detrusor muscles in the walls of the bladder.

The detrusor muscles relax to allow the bladder to fill with pee. It then contracts when you go to the toilet to let the pee out.

Sometimes the detrusor muscles contract too often. This creates an urgent need to go to the toilet. This is known as having an overactive bladder.

The reason your detrusor muscles contract too often may not be clear.

Causes can include:

• drinking too much alcohol or caffeine
• poor fluid intake - can cause strong, concentrated pee to collect in your bladder and irritate it and cause symptoms of overactivity
• constipation
• conditions affecting the lower urinary tract for example, urinary tract infections (UTIs) or tumours in the bladder
• neurological conditions
• some medicines

Causes of overflow incontinence

Overflow incontinence is often caused by a blockage or obstruction of your bladder.

Your bladder may fill up as usual. But as it's obstructed you will not be able to empty it completely, even when you try.

At the same time, pressure from the pee that's still in your bladder builds up behind the obstruction. This can cause frequent leaks.

Your bladder can become obstructed as a result of:

• an enlarged prostate gland in men
• bladder stones
• constipation

Overflow incontinence can also be caused by your detrusor muscles not fully contracting. This means your bladder does not completely empty when you go to the toilet. As a result, your bladder becomes stretched.

Your detrusor muscles may not fully contract if:

• there's damage to your nerves – this could be as a result of surgery to part of your bowel or a spinal cord injury
• you're taking certain medicines

Causes of continuous incontinence

Continuous incontinence happens when your bladder cannot store any pee. It can result in you peeing large amounts all the time, or peeing every now and again with frequent leaking.

Continuous incontinence can be caused by:

• a problem with your bladder from birth
• injury to your spinal cord – this can disrupt the nerve signals between your brain and your bladder
• a bladder fistula – this is a small, tunnel-like hole that can form between the bladder and a nearby area, such as the vagina, in women

Medicines that may cause incontinence

Some medicines can disrupt the normal process of peeing and storing pee. They can also increase the amount of pee you produce.

These include:

• angiotensin-converting enzyme (ACE) inhibitors
• diuretics
• some antidepressants
• hormone replacement therapy (HRT)
• sedatives

Stopping these medicines may help resolve your incontinence. Do not stop taking medicines unless told to by your GP.

Risk factors

Some things increase your risk of developing urinary incontinence without being the cause.

These include:

• family history – you may be more at risk if other people in your family have experienced the problem
• age – it is more common in middle age and quite common in people over 80
• having obstructive lower urinary tract symptoms (LUTS)