One of the more common causes of bedwetting in children is to do with the bladder. There’s a few factors here so I’ll go through them individually. 

We’ll start with the first one - which is a small functional bladder capacity. So what is this?

Some children with bedwetting have bladders that can only hold a small amount of urine. So this prevents the child from sleeping through the night without wetting the bed. Children with small functional bladder capacity have normal-sized bladders, but what’s happening is, their body is sensing a full bladder even when their bladder could still hold more urine. 

These children tend to do wee more often during the day and may even have a sudden urge to rush off to the toilet before wetting themselves. So these children are more likely to wet the bed during the night.  

The other bladder issue is lack of the signal that stops the bladder emptying during the night. To help you understand this better, we’ll go back one step. In babies and toddlers, links between the brain and the bladder have not fully formed. So the bladder just releases urine whenever it feels full. Which is why we need nappies!

As children get older, the connections between the brain and bladder develop. This allows a child to control when the bladder empties. This control usually develops during the daytime first, and takes more time before it happens at night. 

So normally, at night, as the bladder fills with urine, it sends a signal to the brain, which sends a signal back to the bladder to relax so it can hold more urine. So when the bladder is full, the bladder will continue to send signals to the brain so the child will wake up. So if a child has not yet learned to respond to these internal signals, then they’ll wet the bed. 

The next bladder issue can be an overactive bladder. This is when the bladder may contract or spasm and cause the sensation of needing to do wee, even when it isn’t full. This is the most common cause of daytime wetting in children.

An overactive bladder is often not diagnosed until the child is 5 or 6 years old. The most common symptom of an overactive bladder in children is the urge to go to the toilet more often than normal, which is more than 8 times a day. 

Other signs can be the urge to need to wee but nothing comes out, frequent urinary tract infections or wetting accidents during the day. But what if your child doesn’t tell you that they have the urge to wee? How would you know?

You can look for other signs like squirming in their seat, dancing around or jumping from one foot to the other! Also encourage your child to let you know when they need to go to the toilet. If you do suspect your child may have an overactive bladder, I strongly advise you to make an appointment with their doctor, especially if your child is 7 years or older. 

The last bladder issue I’m going to talk about is urinary tract infections. This is another reason why children can wet the bed. Although UTI’s are easily treatable, they can often go initially undiagnosed in children, as sometimes children don’t have the ability to explain their symptoms. Some common symptoms of urinary tract infections are frequent and unexpected trips to the toilet, the feeling of pain when they wee or pain above the pubic bone, difficulty weeing, bad-smelling urine or even blood in the urine. 

Again, if you suspect your child may be suffering from a UTI, then please schedule an appointment with their doctor for an assessment.