Bedwetting may run in families. A gene for enuresis may have been found, which may show some hope for parents, as many children who wet the bed have a parent or other close relative who wet the bed. If you wet the bed as a child, your child will probably stop wetting the bed at about the same age as you did.

Here are some theories on a few things which may contribute to a toddler, child or even a teen having primary or secondary enuresis:

Immature Bladder: some children, teens, and even adults can have a relatively small bladder that can't hold a large volume of urine. In some people, neurological problems can be occurring. Also too many muscle spasms can occur in the bladder, preventing the bladder from holding a useful amount of fluid.

Genetics: scientists have identified a gene that causes enuresis. Often children and teens with nocturnal enuresis have a parent or other close relative who had the same problem.

Medical Conditions: Diabetes, constipation, and urinary tract infections, as well as injury to the spinal cord can cause secondary enuresis.

Deep sleep or other sleep problems can cause primary or secondary enuresis. These children or, occasionally, teens do not wake up when their bodies need to urinate.

Emotional or psychological stresses: starting school, moving, divorce, or a tragedy such as a death can cause stress to the body and lead to secondary enuresis.

Hormonal issues - some people produce less of the anti-diuretic hormone, and thus do not decrease urine production in the night.

In several studies, it has been found that older children and teens with primary or secondary enuresis also have difficulties with constipation. It was also found that dealing with the constipation and other issues voiding lead to a cessation of both primary and secondary enuresis.