Enuresis refers to involuntary urination, most often by children at night. For many children, enuresis, or nighttime bed-wetting, is a major problem that requires further attention. Bed-wetting is caused by a variety of factors such as unusually deep sleep or having a small, dysfunctional bladder. Although typically experienced by children, bed-wetting does not go away as the child ages, therefore some adults who have not been treated at a young age will continue to urinate in their sleep into adulthood.