Enuresis is NOT due to drinking too much fluid, laziness, desire to irritate the parents, or emotional problems, although emotional problems may result from the condition.
Although some may have a bladder that is slightly smaller than average, most children do not have physical abnormalities. Remaining dry at night requires neurological maturation, which varies for individual children.
A possible cause of enuresis is an abnormal regulation of a brain hormone called ADH (antidiuretic hormone), which determines the way that water is retained in the body. In some children with enuresis too little ADH is released at night, so that their bodies produce more urine than the bladder can handle.
According to learning theory, children who achieve nighttime control do so through learning either to wake up and go to the bathroom or to inhibit urination once the first signals of a full bladder are experienced.
Some predisposing factors have been suggested, including delayed or lax toilet training, psychosocial stress, a dysfunction in the ability to concentrate urine, and a lower bladder volume threshold for involuntary voiding.