Bedwetting: What Causes It?

It’s deep in the middle of the night, and you are changing your child’s sheets for the second night in a row this week. They are staring up at you sleepily with an embarrassed look on their face. “Why is my child still wetting the bed?” you ask yourself for what seems like the millionth time. Unfortunately, there is no easy answer to that question, experts say.

Bladder control is a complex process that involves coordinated action between the nerves, muscle, spinal cord and the brain. Development and maturity is a key element of this process, allowing children to stay dry at night. First, children begin producing an antidiuretic hormone between two- and six-years-old that reduces urine output at night, keeping little bladders from getting full until the morning. The second physical process that keeps beds dry at night is the growth and maturation of your child’s bladder. As they age, your child’s bladder grows in size and its ability to sense bladder fullness at night. Together, these physical processes allow children to wake up dry in the morning.

Common Causes

Many bodies are just not developmentally ready for staying dry at night. As a result, the best “treatment” for most bedwetters (particularly those that have never achieved nighttime dryness) is good old fashioned time. With time, the key antidiuretic hormone begins production and bladders grow big enough to handle nighttime duties.

Experts have found that bedwetting tends to run in families. The American Academy of Child and Adolescent Psychiatry found that 44% of children wet the bed if they had one parent with a history of bedwetting, while 77% of children with both parents carrying a history of wetting the bed. Compare those numbers to 15% of children with no family history of bedwetting and it seems pretty clear that genetics play a large part in the story of bedwetting.

Some children who are fully potty trained (during the day and at night) may begin having nighttime accidents (called secondary nocturnal enuresis) following a period stress. Changes in a child’s life related to problems at school, loss of a loved one, divorce, a move, or a new sibling have all been associated with bedwetting in children who were previously completely potty-trained. In a few instances, children who wet the bed may have deeper emotional issues. Typically, a child who is a struggling emotionally will exhibit symptoms other than just bedwetting; they will appear sad or get easily frustrated. If your child appears to be struggling to cope emotionally, and they are wetting the bed, make an appointment with your pediatrician to discuss their symptoms.

Children occasionally develop urinary tract infections or obstruction of the urinary tract that may lead to nighttime accidents. Typically, other symptoms are present, including straining during urinating, cloudy urine, or redness/rash in the genital area. Generally, experts recommend that parents remain patient if their child is having trouble staying dry at night and they are under the age of 7. However, if they are under the age of 7, and they have any of the above co-occurring symptoms, parents should take their child to the pediatrician to explore possible medical causes.