Why a teen at age 14 would still be suffering from nocturnal enuresis?

Many reasons: Noctunal enuresis in a 14 year old is a serious condition and warrants further evaluation by a pediatrican and perhaps a pediatric specialist. I would recommend seeing your pediatrician for further evaluation.

Functional problem: Nocturnal enuresis uncommon at age 14, not very rare amongst patients seeing practicing pediatric urologists. Certainly much more common at an earlier age. Some bed-wetters have reduced functional bladder capacity so that urination needs to occur after relatively minor bladder filling. In others abnormal "circadian rhythm " causes more urine production at night than by day. Anatomic problems rare.

Often normal: 10% of children wet the bed at age 6 years of age. 10% of these children improve with each passing year. See your doctor to make sure that there is nothing serious going on.