What are causes of nocturnal enuresis

Dr. Perri Klass, a pediatrician, explores the challenges of nocturnal enuresis, or bed wetting.

While parents often accuse bedwetters of laziness, the problem can stem from a number of physiological causes.

Some children lack a hormone that decreases urine production at night. Others wet the bed simply because their bladder capacity is small.

“Here’s the encounter I usually have when I see children in my clinic,” Dr. Jennifer Abidari, chief of pediatric urology at the Santa Clara Valley Medical Center in California, told me. “I draw a bunch of bladders, and three of them are big and one of them is very small.

“I ask them which one was wetting and they’ll usually guess the smaller one, and I’ll say, ‘You’re right — you have a bladder that’s smaller than your age, and it’s not your fault.’ And I’ll see the child glance over to the parent and I’ll know there’s been a lot of conflict.”