Getting rid of the overnight diaper is the last step to completing potty training. Children are typically ready for nighttime potty training when they are in regular underwear all day long and wake up dry more often than they wake up wet. Children develop individually, so your child's readiness to switch to underwear at night may differ from that of his peers. If you feel that he is ready, try eliminating his nighttime diaper.
Talk to your child about wearing regular underwear to bed. Discuss how well she has been doing during the day using the toilet, and how she is big enough to try giving up her nighttime diaper. Reminde her that adults and older children do not wear diapers at night, and she is growing up and becoming a big girl.
Implement an evening beverage cutoff time. Try 6:00 p.m. as the time after which your child cannot have anything to drink. Once nighttime potty training is complete, this rule can be changed.
Add sitting on the toilet to the bedtime routine. Try to have your child go to bed with an empty bladder.
Plug in a night light or install a dimmer switch, either in your child's room or in the hallway between the room and the bathroom. Ensure that the floor is clear of toys and there will be nothing for him to trip on if he needs to walk to the bathroom in low light after having just woken up.
Cover her mattress with a plastic mattress protector. Not only will this save the mattress from being damaged if she has an accident, it will also contain the wetness in the spot where she is lying, which will wake her up. Most children find this uncomfortable enough that they soon learn to wake up before they wet themselves.
Be prepared for some extra laundry. If your child has accidents at night, resist the impulse to put him back in a nighttime diaper or disposable training pant.
Motivate your child by recognizing her successes. Allow her to put a sticker on each day of the calendar that she wakes up dry. Positive reinforcement can help her on those nights when she wakes up needing to urinate but does not want to get out of her warm bed.
Get professional help if needed. Some children simply have bladders that are slower to mature. Others have medical issues impeding bladder control that need to be addressed. Consult your doctor if, despite your best efforts, your child continues to wet his bed past the age you feel he should.