What are Common Causes of Enuresis (Bedwetting)?

Being lazy or willful is almost never a reason for a child's loss of bladder control. In a small number of cases, behavior may play a role. No matter the causes, parents need to be patient and supportive. Bedwetting is caused by a combination of things:

Family history (genetics)

Bedwetting can be inherited. The "bedwetting gene" is strong among families. Half of all children who have this problem had a parent who also struggled with bedwetting. This percent increases to 75% if both parents had enuresis. Close relatives (aunts, uncles and grandparents) may also share this gene, though you may not know it. A child without a family connection has only a 15% chance of bedwetting.

Slow development of brain-bladder control

Children who wet their beds are often described as "deep sleepers." Deep sleep affects the way the bladder communicates with the brain. Instead of waking up to use the toilet, the child's pelvic floor muscles relax and empty while the child sleeps. This brain-bladder control will develop naturally over time, or speed up with treatment.

Smaller than expected bladder capacity

Some children who have enuresis have bladders that can only hold a small amount of urine. This condition does not allow the child to sleep through the night without wetting the bed.

Making too much urine while asleep

Your child's kidneys may make too much urine at night, and the bladder may not be able to hold it all. Normally, the brain produces a hormone called "antidiuretic hormone (ADH)" which slows the kidney's urine production. It helps make less urine at night. When the brain does not make enough ADH or when the kidney stops responding to it, more urine is produced. The child will either have to wake up several times during the night to urinate or wet the bed. Caffeinated and carbonated drinks may also cause the kidneys to produce more urine. .

Type 1 diabetes (insulin dependent diabetes mellitus or "sugar diabetes") is caused by a lack of the hormone insulin. This hormone helps manage the sugar we get through food and drink. In untreated patients with type 1 diabetes, sugar is lost in the urine. This leads to a great loss of water. Some children with type 1 diabetes may have bedwetting as a symptom at the start of their illness.]

Sleep disorders

Some children have sleep disorders such as sleepwalking or obstructive sleep apnea (OSA). With OSA, less oxygen from poor breathing will cause the heart to produce "atrial natriuretic peptide (ANP)." This substance will cause the kidneys to produce extra urine at night.


The rectum lies behind the bladder. If constipation causes stool to store in the rectum, it will push on the bladder. This limits the way the bladder can hold urine, causing leaks.


Any form of stress can lead to bedwetting problems. If the stress from bedwetting itself affects your child or your family, it can make things worse. Children who wet the bed often fear being discovered and teased by their friends or siblings. Emotionally, a child can become withdrawn and nervous. Children with learning disorders or attention problems generally feel more stressed. These children commonly have bedwetting issues. Be aware of social stresses that can affect bedwetting, such as:

  • A new brother or sister
  • Sleeping alone
  • Starting a new school
  • A family crisis
  • An accident or trauma