Bedwetting:

Children who have gained nighttime bladder control, then "relapsed" into bedwetting, are slightly more likely to have medical causes. Psychological stress (such as divorce or the birth of a new sibling) is an even more common cause, though.

Pediatricians don't diagnose primary nocturnal enuresis (the medical term for bedwetting) until age 6. It's an arbitrary cutoff -- after all, 12% of children wet the bed at that age. "It's really only a problem when either the child or the parents start to think so,"

The Bedwetting Gene

There's no one single cause of bed-wetting, but if you want an easy target, look no farther than your own DNA.

"The majority of bedwetting is inherited,". "For three out of four kids, either a parent or a first-degree relative also wet the bed in childhood."

Scientists have even located some of the specific genes that lead to delayed nighttime bladder control. (For the record, they're on chromosome 13, 12, and 8.)

"Most parents who had the same problem communicate it to their kids, which is good,". "It helps a kid understand, I'm not alone, it's not my fault."

The Usual Bedwetting Suspects

• Delayed bladder maturation. "Simply put, the brain and bladder gradually learn to communicate with each other during sleep, and this takes longer to happen in some kids".
• Low anti-diuretic hormone (ADH). This hormone tells the kidneys to make less urine. Studies show that some kids who wet the bed release less of this hormone while asleep. More urine can mean more bedwetting.
• Deep sleepers. "Families have been telling us for years that their children who wet the bed sleep more deeply than their kids that don't". Research confirms the link. "Some of these children sleep so deeply, their brain doesn't get the signal that their bladder is full."
• Smaller "functional" bladder. Although a child's true bladder size may be normal, "during sleep, it sends the signal earlier that it's full".. 
• Constipation. Full bowels press on the bladder, and can cause uncontrolled bladder contractions, during waking or sleep. "This is the one that's hiding in the background". "Once kids are toilet trained, parents often don't know how often a child is going ... [they're] out of the 'poop loop.'"

Bedwetting Treatment: Becoming 'Boss of Your Body'

Addressing the problem positively can avoid lasting problems, and numerous strategies can help children cope with and improve bedwetting. Some bed-wetting treatments include:

• Encouraging a child to pee before bedtime.
• Restricting a child's fluid intake before bed.
• Covering the mattress with plastic.
• Bed-wetting alarms. These alarms sense urine and wake a child so they can use the toilet.
• Bladder stretching exercises that may increase how much urine the bladder can hold.
• Medications.