The fizz in the toothpaste is caused by the acid in the urine reacting with the calcium carbonate in the toothpaste to give off carbon dioxide,? he said.
"The more acidic the urine is, the greater the fizz. Whether or not a person is or isn't pregnant wouldn't make any difference.?
"Even if the 'toothpaste test' does appear to be 'positive' I would strongly recommend that any possible mum-to-be gets official confirmation of the fact that they are indeed pregnant with a proper pregnancy test."
How women are using toothpaste as pregnancy tests - but expert reveals huge flaw - Mirror Online