my daughter was around the age of 4 when she stopped. Also cutting back on liquids an hour or so before bedtime helps,,,,,and of course to make them go potty before bedtime.
My daughter is three and if she has anything to drink before she goes to bed she will wet the bed by 4:00a.m. everytime so i have to make sure she does not have anything 30min. to an hour before she goes to bed and also goes to the bathroom if not she will for sure wet the bed.