What should I do about my teenage daughter's bedwetting problem?

Get treatment. Bedwetting can be considered normal up to 7-years. Beyond ten years is definitely abnormal, more so with any daytime symptoms eg urinary frequency. Wetting is due to xs nocturnal urine production, small bladder or nerves immatue get urine tested if normal restrict fluids after 6-7pm, then toilet about 2 hours after she goes to bed, providing you are still up and about. Then try a bedwetting alarm.
Talk w/ Pediatrician. Bed wetting is actually normal up until about the age of 12. However, if bed wetting persists beyond that age, it is time to have a discussion with your pediatrician. It may be a physical problem with the muscles that keep the bladder closed until one is ready to urinate, or it could be a psychological issue, or a combination thereof. Your pediatrician can best advise you on a course of action.
Bed wetting. Bed wetting in teenage girls is an indication of a bigger problem like urinary tract infection or diabetes or local infection. Check with your physician about being checked.