Nocturnal enuresis or nighttime urinary incontinence, commonly called bedwetting, or "'sleepwetting'" is involuntary urination while asleep after the age at which bladder control usually occurs. Nocturnal enuresis is considered primary (PNE) when a child has not yet had a prolonged period of being dry. Secondary nocturnal enuresis (SNE) is when a child or adult begins wetting again after having stayed dry.
Bedwetting is the most common childhood urologic complaint  and one of the most common pediatric-health issues. Most bedwetting, however, is just a developmental delay—not an emotional problem or physical illness. Only a small percentage (5% to 10%) of bedwetting cases are caused by specific medical situations. Bedwetting is frequently associated with a family history of the condition.
Most girls can stay dry by age six and most boys stay dry by age seven. By ten years old, 95% of children are dry at night. Studies place adult bedwetting rates at between 0.5% to 2.3%.
Treatments range from behavioral-based options such as bedwetting alarms, to medication such as hormone replacement, and even surgery such as urethral enlargement. Since most bedwetting is simply a developmental delay, most treatment plans aim to protect or improve self-esteem. Bedwetting children and adults can suffer emotional stress or psychological injury if they feel shamed by the condition. Treatment guidelines recommend that the physician counsel the parents, warning about psychological damage caused by pressure, shaming, or punishment for a condition children cannot control.
The medical name for bedwetting is nocturnal enuresis. The condition is divided into two types: primary nocturnal enuresis (PNE) and secondary nocturnal enuresis.
Primary nocturnal enuresis (PNE)
Primary nocturnal enuresis (PNE) is the most common form of bedwetting. Bedwetting counts as a disorder once a child is old enough to stay dry, but continues either to average at least two wet nights a week with no long periods of dryness or to not sleep dry without being taken to the toilet by another person.
Medical guidelines vary on when a child is old enough to stay dry. Common medical definitions allow doctors to diagnose PNE beginning at between 4 to 5 years old. This type of classification is frequently used by insurance companies. It defines PNE as, "persistent bedwetting in the absence of any urologic, medical or neurological anomaly in a child beyond the age when over 75% of children are normally dry."
Some researchers, however, recommend a different starting age range. This guidance says that bedwetting can be considered a clinical problem if the child regularly wets the bed after turning seven years old. D'Alessandro refines this to bedwetting more than twice a month after six years old for girls and seven years old for boys.
Secondary nocturnal enuresis
Secondary enuresis occurs after a patient goes through an extended period of dryness at night (roughly six months or more) and then reverts to nighttime wetting. Secondary enuresis can be caused by emotional stress or a medical condition, such as a bladder infection.
U.S. psychological definition
Psychologists may use a definition from the American Psychiatric Association's DSM-IV, defining nocturnal enuresis as repeated urination into bed or clothes, occurring twice per week for at least three consecutive months in a child of at least 5 years of age and not due to either a drug side effect or a medical condition. Even if the case does not meet these criteria, the DSM-IV definition allows psychologists to diagnose nocturnal enuresis if the wetting causes the patient clinically significant distress.
The following list summarizes bedwetting's known causes and risk factors. Enuretic patients frequently have more than one cause or risk factor from the items listed below.
Most cases of bedwetting are PNE-type, which has two related most common causes
Neurological-developmental delay This is the most common cause of bedwetting. Most bedwetting children are simply delayed in developing the ability to stay dry and have no other developmental issues. Studies suggest that bedwetting may be due to a nervous system that is slow to process the feeling of a full bladder.
Genetics Bedwetting has a strong genetic component. Children whose parents were not enuretic have only a 15% incidence of bedwetting. When one or both parents were bedwetters, the rates jump to 44% and 77% respectively. Genetic research shows that bedwetting is associated with the genes on chromosomes 13q and 12q (possibly 5 and 22 also).
These first two items are the most common factors in bedwetting, but current medical technology offers no easy testing for either cause. There is no test to prove that bedwetting is only a developmental delay, and genetic testing offers little or no benefit.
As a result, doctors work to rule out other causes. The following causes are less common, but are easier to prove and more clearly treated:
Insufficient anti-diuretic hormone (ADH) production A portion of bedwetting children do not produce enough of the anti-diuretic hormone. As explained above, the body normally increases ADH levels at night, signalling the kidneys to produce less urine. The diurnal change may not be seen until about age 10.
More severe neurological-developmental issues Patients with intellectual disabilities have a higher rate of bedwetting problems. One study of seven-year-olds showed that "handicapped and intellectually disabled children" had a bedwetting rate almost three times higher than "non-handicapped children" (26.6% vs. 9.5%, respectively).
Physical abnormalities Less than 10% of enuretics have urinary tract abnormalities, such as a smaller than normal bladder. Current data does support increased bladder tone in some enuretics, which functionally would decrease bladder capacity.
Psychological Psychological issues (e.g., death in the family, sexual abuse, extreme bullying) are established as a cause of secondary nocturnal enuresis (a return to bedwetting), but are very rarely a cause of PNE-type bedwetting. Bedwetting can also be a symptom of a pediatric neuropsychological disorder called PANDAS. When enuresis is caused by a psychological or neuropsychological disorder, the bedwetting is considered a symptom of the disorder. Enuresis has a psychological diagnosis code (see previous section), but it is not considered a psychological condition itself. (See section on psychological/social impact, below)
Sleepwalking Sleepwalking can lead to bedwetting. During sleepwalking, the sleepwalker may think he/she is in another room. When the sleepwalker urinates during a sleepwalking episode, he/she usually thinks they are in the bathroom, and therefore urinate where they think the toilet should be. Cases of this have included opening a closet and urinating in it; urinating on the sofa and simply urinating in the middle of the room.
Stress Stress is not a cause of primary nocturnal enuresis (PNE), but is well established as a cause of returning to bedwetting (secondary nocturnal enuresis). Researchers studying children who have yet to stay dry find "no relationship to social background, life stresses, family constellation, or number of residencies." On the other hand, stress is a cause of people who return to wetting the bed. Researchers find that moving to a new town, parent conflict or divorce, arrival of a new baby, or loss of a loved one or pet can cause insecurity, contributing to returning bedwetting.
Unconfirmed, controversial, or mixed causes
Heavy sleeping Many parents report that their bedwetting children are heavy sleepers. Research in this area has produced some contradictory results. Studies show that children wet the bed during all phases of sleep, not just the deepest (stage four, or stages three and four). A recent study, however, showed that enuretic children were harder to wake up. Some literature does show a possible connection between sleep disorders and ADH production. Insufficient ADH might make it more difficult to transition from light sleep to being awake.
Improper toilet training This is another disputed cause of bedwetting. This theory was more widely supported in the last century and is still cited by some authors today. Some say bedwetting can be caused by improper toilet training, either by starting the training when the child is too young or by being too forceful. Recent research has shown more mixed results and a connection to toilet training has not been proven or disproven.
Dandelions Anecdotal reports and folk wisdom say children who handle dandelions can end up wetting the bed. Dandelions are reputed to be a potent diuretic. English folk names for the plant are "peebeds" and "pissabeds". In French dandelions are called pissenlit, which means "urinate in bed"; likewise "piscialletto", an Italian folkname, and "meacamas" in Spanish.
A review of medical literature shows doctors consistently stressing that a bedwetting child is not at fault for the situation. Many medical studies state that the psychological impacts of bedwetting are more important than the physical considerations. "It is often the child's and family member's reaction to bedwetting that determines whether it is a problem or not."
Impact on self-esteem
Whether bedwetting causes low self-esteem remains a subject of debate, but several studies have found that self-esteem improved with management of the condition. Children questioned in one study ranked bedwetting as the third most stressful life event, after parental divorce and parental fighting. Adolescents in the same study ranked bedwetting as tied for second with parental fighting.
Bedwetting children face problems ranging from being teased by siblings, being punished by parents, and being afraid that friends will find out.
Psychologists report that the amount of psychological harm depends on whether the bedwetting harms self-esteem or development of social skills. Key factors are:
How much the bedwetting limits social activities like sleep-overs and campouts
The degree of the social ostracism by peers
Anger, punishment, and rejection by caregivers
The number of failed treatment attempts
How long the child has been wetting
Studies show that bedwetting children are more likely to have behavioral problems. For children who have developmental problems, the behavioral problems and the bedwetting are frequently part of/caused by the developmental issues. For bedwetting children without other developmental issues, these behavioral issues can result from self-esteem issues and stress caused by the wetting.
As mentioned below, current studies show that it is very rare for a child to intentionally wet the bed as a method of acting out.
Historical psychological perspective on bedwetting
"Urinating in bed is frequently predisposed by deep sleep: when urine begins to flow, its inner nature and hidden will (resembling the will to breathe) drives urine out before the child awakes. When children become stronger and more robust, their sleep is lighter and they stop urinating."
Psychological theory through the 1960s placed much greater focus on the possibility that a bedwetting child might be acting out, purposefully striking back against parents by soiling linens and bedding. (More recent research and medical literature states that this is very rare.)
Punishment for bedwetting: effects and rates
Medical literature states and studies show that punishing or shaming a child for bedwetting will frequently make the situation worse. Doctors describe a downward cycle where a child punished for bedwetting feels shame and a loss of self-confidence. This can cause increased bedwetting incidents, leading to more punishment and shaming.
In the United States, about 25% of enuretic children are punished for wetting the bed. In Hong Kong, 57% of enuretic children are punished for wetting. Parents with only a grade-school level education punish bedwetting children at twice the rate of high-school- and college-educated parents.
Impact on families
Parents and family members are frequently stressed by a child's bedwetting. Soiled linens and clothing cause additional laundry. Wetting episodes can cause lost sleep if the child wakes and/or cries, waking the parents. A European study estimated that a family with a child who wets nightly will pay about $1,000 a year for additional laundry, extra sheets, disposable absorbent garments such as diapers, and mattress replacement.
Despite these stressful effects, doctors emphasize that parents should react patiently and supportively.
Research has shown that bedwetting does not indicate a greater possibility of being a sociopath, as long as caregivers do not cause trauma by shaming or punishing a bedwetting child. Bedwetting was part of the Macdonald triad, a set of three behavioral characteristics described by John Macdonald in 1963. The other two characteristics were firestarting and animal abuse. Macdonald suggested that there was an association between a person displaying all three characteristics, then later displaying sociopathic criminal behavior.
Research has found, however, that enuresis is not associated with sociopathic behavior. Enuresis is an “unconscious, involuntary, and nonviolent act and therefore linking it to violent crime is more problematic than doing so with animal cruelty or firesetting".
Bedwetting can be connected to emotional or physical trauma. Trauma can trigger a return to bedwetting (secondary enuresis) in both children and adults. In addition, caregivers cause some level of emotional trauma when they punish or shame a bedwetting child.
This leads to a difficult distinction: it is not the bedwetting that increases the chance of criminal behavior, but the trauma. For example, parental cruelty can result in "homicidal proneness".
There are a number of treatment and condition management options for bedwetting. The following options apply when the bedwetting is not caused by a specifically identifiable medical condition such as a bladder abnormality or diabetes.
When treatment is recommended
Doctors consider treatment when there is a specific medical condition such as bladder abnormalities, infection, or diabetes. Physicians also treat bedwetting when it may harm the child's self-esteem or relationships with family/friends. Only a small percentage of bedwetting is caused by a specific medical condition, so most treatment is prompted by concern for the child's emotional welfare. Behavioral treatment of bedwetting overall tends to show increased self-esteem for children 
Parents become concerned much earlier than doctors. A study in 1980 asked parents and physicians the age that children should stay dry at night. The average parent response was 2.75 years old, while the average physician response was 5.13 years old.
Punishment is not effective and can interfere with treatment.
Treatment options with high success rates
Waiting Almost all children will outgrow bedwetting. For this reason, urologists and pediatricians frequently recommend delaying treatment until the child is at least six or seven years old. Physicians may begin treatment earlier if they perceive the condition is damaging the child's self-esteem and/or relationships with family/friends.
Bedwetting alarms Physicians also frequently suggest bedwetting alarms which sound a loud tone when they sense moisture. This can help condition the child to wake at the sensation of a full bladder. These alarms are considered effective, with study participants being 13 times more likely to become dry at night. There is a 29% to 69% relapse rate, however, so the treatment may need to be repeated.
DDAVP (desmopressin) Desmopressin tablets are a synthetic replacement for antidiuretic hormone, the hormone that reduces urine production during sleep. Desmopressin is usually used in the form of desmopressin acetate, DDAVP. Patients taking DDAVP are 4.5 times more likely to stay dry than those taking a placebo. The drug replaces the hormone for that night with no cumulative effect. US drug regulators have banned using desmopressin nasal sprays for treating bedwetting since the oral form is considered safer.
Absorbent Underwear Absorbent underwear or diapers can reduce embarrassment for bedwetters and make cleanup easier for caregivers. These products are known as training pants or diapers when used for younger children, and as absorbent underwear or incontinence briefs when marketed for older children and adults. Some brands of diaper are marketed especially for sufferers of bedwetting. A major benefit is the reduced stress on both the bedwetter and caregivers. Absorbent underwear can be especially beneficial for bedwetting children wishing to attend sleepovers or campouts, reducing emotional problems caused by social isolation and/or embarrassment in front of peers. Extended diaper usage may interfere with learning to stay dry at night, at least in adults with severe disabilities.
Waterproof mattress pads are used in some cases to ease clean-up of bedwetting incidents, however they only protect the mattress, and the sheets, bedding or sleeping partner may be soiled.
Unproven/ineffective treatment options
Acupuncture While acupuncture is safe in most adolescents, studies done to assess its effectiveness for nocturnal enuresis are of low quality.
Dry bed training Dry bed training consists of a strict schedule of waking the child at night, attempting to condition the child into waking by himself/herself. Studies show this training is ineffective by itself and does not increase the success rate when used in conjunction with a bedwetting alarm.
Star chart A star chart allows a child and parents to track dry nights, as a record and/or as part of a reward program. This can be done either alone or with other treatments. There is no research to show effectiveness, either in reducing bedwetting or in helping self-esteem. Some psychologists, however, recommend star charts as a way to celebrate successes and help a child's self-esteem.
Two physical functions prevent bedwetting. The first is a hormone that reduces urine production at night. The second is the ability to wake up when the bladder is full. Children usually achieve nighttime dryness by developing one or both of these abilities. There appear to be some hereditary factors in how and when these develop.
The first ability is a hormone cycle that reduces the body's urine production. At about sunset each day, the body releases a minute burst of antidiuretic hormone (also known as arginine vasopressin or AVP). This hormone burst reduces the kidney's urine output well into the night so that the bladder does not get full until morning. This hormone cycle is not present at birth. Many children develop it between the ages of two and six years old, others between six and the end of puberty, and some not at all.
The second ability that helps people stay dry is waking when the bladder is full. This ability develops in the same age range as the vasopressin hormone, but is separate from that hormone cycle.
The typical development process begins with one- and two-year-old children developing larger bladders and beginning to sense bladder fullness. Two- and three-year-old children begin to stay dry during the day. Four- and five-year-olds develop an adult pattern of urinary control and begin to stay dry at night.
Most girls can stay dry at night by age six and most boys stay dry by age seven. Boys are three times more likely to wet the bed than girls.
Doctors frequently consider bedwetting as a self-limiting problem, since most children will outgrow it. Children 5 to 9 years old have a spontaneous cure rate of 14% per year. Adolescents 10 to 18 years old have a spontaneous cure rate of 16% per year.
As can be seen from the numbers above, a portion of bedwetting children will not outgrow the problem. Adult rates of bedwetting show little change due to spontaneous cure. Persons who are still enuretic at age 18 are likely to deal with bedwetting throughout their lives.
Studies of bedwetting in adults have found varying rates. The most quoted study in this area was done in the Netherlands. It found a 0.5% rate for 18- to 64-year-olds. A Hong Kong study, however, found a much higher rate. The Hong Kong researchers found a bedwetting rate of 2.3% in 16- to 40-year-olds.