At What Age Do Kids Gain Control of Their Bladder?

If your best friend is holding her six-month-old over the toilet every few hours and claiming the baby is trained, you might look askance at your 2-year-old and wonder why she isn't getting this "wetting on demand" thing. Infant bladder training, also known as elimination communication, is all the rage in some circles today. But most American kids don't achieve true bladder control for a few more years, between 18 and 24 months or, in some cases, not until age 30 months, although early toilet training is common in other parts of the world.

Defining Bladder Control

If you define bladder control as your little one's ability to recognize signs that urination is imminent, take himself to the bathroom, undress, sit on the potty, go and then get cleaned up and dressed, obviously bladder control isn't achieved by infants. But if you define it as the ability to go on demand and to hold urine for a very short time, you might be able to bladder train an infant. For most kids, bowel control precedes bladder control and staying dry during the day comes before staying dry all night. Each kid is an individual and will develop bladder control at a different age.

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Traditional Potty Training

Traditional potty training in the United States means waiting until your child shows an awareness that he needs to use the potty, develops an interest in urinating like everyone else does and is able to sit on some sort of urine-containing pot, whether it be a child's potty or the commode. Being able to pull pants up and down -- a skill girls master around 29.5 months and boys around 33.5 months, according to Beth Choby, M.D., assistant professor at the University of Tennessee–Chattanooga -- is also helpful for kids who tend to rush to the potty at the last minute. If your child can stay dry for two hours on his own, he has the bladder control to start potty training.

Average Age

The average age for toilet training in the United States is 29 months for girls and 31 months for boys, with 98 percent of kids trained during the daytime by age 36 months, according to the staff of the University of Michigan Health System. This is a big change from four decades ago, when kids were typically trained before 18 months of age, Choby says. For traditional potty training, there seems to be no advantage to starting intensive training before age 27 months; intensive training means asking your child three or more times a day to try using the potty.

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When Not to Train

The Mayo Clinic stresses that starting potty training when your child is already under stress from a move, a new baby in the house, starting preschool or any other major stress isn't a good idea. Shaming your child, getting angry when he has an accident, or using words with a negative connotation to describe normal bodily functions is counterproductive and can result in your child not being willing to let go of his precious bodily fluids, since you value them so little. It's also not a good idea to let other people -- like your parents -- shame you into starting potty training if you know your child isn't ready for it.

Wetting Accidents After Toilet Training

Accidents happen, especially in the first six months to one year after your child is potty trained. Daytime accidents normally decrease in frequency until they occur only rarely by age 6. Kids who continue to have frequent accidents during the day or night, especially if wetting occurs after previously successful training, might need medical evaluation for diabetes mellitus, which causes increased urination. An immature nervous system, lack of recognition that the bladder is full or constipation, which puts pressure on the bladder, can also cause bed-wetting. One of of four kids still wet the bed at night at age 5, the American Academy of Pediatrics explains, with boys making up 66 percent of bed-wetters.

Suzanne Robin is a registered nurse with more than 25 years of experience in oncology, labor/delivery, neonatal intensive care, infertility and ophthalmology. She also has extensive experience working in home health with developmentally delayed or medically fragile children. Robin received her RN degree from Western Oklahoma State College. She has coauthored and edited numerous books for the Wiley "Dummies" series.

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