What causes bedwetting? It’s about what happens in a child’s brain.

Many parents want to know the reasons their child wets the bed.

It’s simple: bedwetting almost always happens because a child’s brain has not learned to link needing to pee with waking and going to the loo.

Facts on bedwetting causes

• Bedwetting is hereditary (runs in families): children are more likely to wet the bed if one or both parents have a history of bedwetting at the same age.
• Bedwetting is uncommon:
• more than half of children are dry at night by age 3 years 6 months
• just 1 in 5 wet the bed at age 5
• fewer than 1 in 50 wet the bed at age 15.
• bedwetting is more common for boys than girls because girls' brains develop faster.
• Bedwetting isn't usually caused by psychological trauma.
• Bedwetting is more common for children with special needs, learning disabilities and developmental disorders like autism, ADHD and Down Syndrome, but wetting the bed does not mean the child has a disorder.
• Bedwetting is more common in children who are deep sleepers, but deep sleep does not cause bedwetting.
• Sometimes a child who was once dry at night starts to wet the bed again around emotional life events, like a sibling birth, house move or change of school. This is sometimes called 'regression'. Their brain is doing a lot of work and growing at these times!
• Children do not wet the bed for attention, to annoy parents or because they're lazy.

Medical problems linked to bedwetting

In rare cases, a child will have a medical problem that needs treating before tackling the child's bedwetting. These include bladder infection (UTI), constipation and low Antidiuretic hormone (ADH) levels. If you think any of these may apply to your child, visit a doctor.

Read next: How to stop bedwetting with an alarm

Take the first step: Download our free Night Toilet Training Guide