Paediatric urologist Dr Steve Hodges said mums and dads who toilet train their kids before the age of three could be inadvertently causing constipation, kidney damage and even urinary tract infections because the toddlers are holding onto their urine and bowel movements longer than they should.
And the professor at Wake Forest University in North Carolina, says that training too early can lead to more toilet accidents because the bladder may not be strong enough.
"Children under age three should not manage their own toileting habits any more than they should manage their college funds," Dr Hodges told Babble.com.
He has written a book, It's No Accident, to debunk myths that parents should strive to get their children out of nappies and onto toilets at earlier and earlier ages.
He said that babies need to experience 'uninhibited voiding', or elimination, in a way they can respond to their bodies urges in a judicious manner. Once they fully figure that out, then parents can bring them to the bathrooms.
When parents train too early, eager to brag about their 'Potty Prodigies,' it can lead to devastating problems in the future.
"Virtually all toileting problems – pee and poop accidents, bedwetting, urinary frequency, and urinary tract infections – are related to chronically holding pee or poop or both," he wrote.
"It's typically the kids who trained earliest and most easily who develop the most serious problems."
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