What Is Nocturnal Enuresis (Bedwetting)?

Female Urinary Tract

Male Urinary Tract

When children urinate without control while they sleep, it is called nocturnal enuresis. It's also known as bedwetting.

Most children can control their bladder during the day and night by the age of 4. About 10% of children age 6 or 7 still can't stay dry, as they have day or nighttime "accidents." If a child experiences bladder control problems during sleep after the age of 7, it's worth looking into. Your health care provider can help.

Nocturnal enuresis is common for more than 5 million children in the U.S. It is slightly more common in boys than girls. This issue can be frustrating for children, parents and health care providers. As children spend more nights away from home (at camps, sleepovers and field trips), it is more imperative tolook for solutions. With patience and tools for treatment, most children will stop bedwetting.

There are two types of nocturnal enuresis. The testing, care and treatment for both types are very similar:

  • Primary nocturnal enuresis describes children who never achieved dry nights since potty training (typically these children have no accidents during the day time)

  • Secondary nocturnal enuresis is when a child achieved consistent dry nights for at least six months but has now started bedwetting again. Mostly, this type of bedwetting is related to a stressful event (e.g. birth of a sibling, parent divorce, etc.). Eating disorders and some medicines can cause secondary bedwetting.

Contact your pediatrician if your child is experiencing either of these types of nocturnal enuresis

How Does the Urinary System Work?

Urine is liquid waste from your body. Urine forms when the kidneys clean your blood. The "urinary tract" includes the organs in your body that make, store and remove urine.

Normally, the kidneys make about 1½ to 2 quarts of urine each day in an adult; less in children. Urine travels from the kidneys to the bladder through the ureters (the tubes that join them). The bladder has the job of storing and releasing urine. The muscular neck of the bladder stays closed in order to store urine. The urethra is the tube that carries urine from the bladder, out of the body. This area is kept closed with sphincter muscles.

The brain works with the bladder to control when to release urine. Once you are ready to release urine (i.e.: in a toilet), the brain sends a signal to the bladder. Then the bladder muscles contract. This pushes urine out of the bladder, through the urethra. The sphincter muscles open, and urine is released out of the body.

At first, infants release urine in an uncontrolled way by a simple reflex. As infants grow, several things develop to allow them to gain control over the way their bladder empties:

  • The bladder grows to hold more urine volume with age. 
  • By age 2-3 years, the child gains control over the sphincter and pelvic floor muscles. When they squeeze these muscles, children can hold the flow of urine until they reach to a toilet. 
  • The brain matures with age to allow children to relax or squeeze these muscles at all times. This is when they become "toilet trained." 
  • By age 7, 90% of children can control their bladder both day and night. If they have to use the bathroom at night, they will wake up and go.