Bed-wetting is normal and very common among preschoolers, affecting 40 percent of children at age three. It is much less frequent in school-age children, occurring in 20 percent of five-year-olds, 10 percent of six-year-olds, and 3 percent of twelve-year-olds. Thus, during the middle years of childhood, parents may want to seek the assistance of their pediatrician in an effort to reduce or eliminate bed-wetting, or enuresis.
For a child to remain dry at night, her brain must keep a full bladder from emptying. Or a signal from the bladder must be strong enough to awaken the child from sleep and send her to the toilet. It is a complex neurodevelopmental process for the bladder to send the signal, for the brain to receive it, and for the child to respond by awakening and using the toilet.
There are many theories about the causes of bed-wetting. Many parents fear that a disease is causing the difficulty. However, no more than 1 percent of cases actually are related to physical diseases such as kidney or bladder infections, diabetes, or congenital defects of the urinary system. In these instances the child also generally experiences changes in the frequency and volume of daytime urination, or discomfort associated with urination.
In the majority of cases of bed-wetting, however, the cause is simply delayed maturation of bladder control mechanisms, often related to the child's genetic background. These children are physically and psychologically normal.
Emotional problems are an occasional cause of enuresis. For instance, a child who is overwhelmed with stress may develop enuresis, even though she had formerly been dry at night. Children who are being sexually or physically abused may also develop enuresis.
Most school-age children who wet their beds have primary enuresis, meaning they have had this condition since birth and have never developed nighttime bladder control. These children often have a family history of this problem, and they seem to have inherited the tendency for developing nighttime bladder control at a later-than-average age. In most cases the child becomes dry at about the same age that her parent(s) did. Interestingly, if one identical twin has a bed-wetting problem, her twin also will; however, fraternal twins (non-identical twins with different genetic makeups) often do not both have this problem.
Sometimes parents pressure a child to develop nighttime bladder control before her body is ready to do so. These parents may erroneously view bed-wetting as a willful and oppositional act of their child, and thus they may try coercing her to change her behavior. The youngster may become discouraged and depressed when she continues to wet the bed. As hard as she may try, the enuresis is beyond her voluntary control, and she may become frustrated and despondent because of her lack of success.
For the child who wets the bed, parents need to remain supportive and encouraging. They should be sensitive to the child's embarrassment or discomfort over this problem. The youngster may resist spending the night at a friend's house or going to summer camp and may be uncomfortable about her friends' finding out about this condition. Parents can reassure the child that it is not her fault, and the problem will get better in time.