A doctor has confirmed that, no, weeing on toothpaste is not a reliable pregnancy test.

A doctor has warned against using do-it-yourself toothpaste pregnancy tests.

The trend has gathered traction online with over a million views on some how-to videos on YouTube.

One video instructs viewers to prepare urine in a cup, add toothpaste to a bowl and then “pour some drops of the urine into the toothpaste”.

The video claims you are “positively pregnant” if the toothpaste changes to look blue(ish) and foamy after stirring.

Fertility Specialist and Gynaecologist, Dr Sonya Jessup, says it's not at all a reliable method.

"In my experience, even over the counter 'wee on a stick' pregnancy tests can give dubious and false results," she told Mamamia.

"The amount of false hope or despair this less than accurate test could cause is not worth the risk in my opinion."

A pregnancy test checks a woman’s blood or urine for the presence of a substance called human chorionic gonadotropin (hCG) - a hormone made by the placenta.

In March, more than a dozen home pregnancy tests were been pulled from supermarket shelves after regulators found some tests were giving false results.

An Australian family planning clinic alerted the Therapeutic Goods Administration (TGA) after three pregnant women used the One Step HCG urine pregnancy test and were given a false negative result.

The kit was tested and found to be “insensitive” to detecting hCG.

Consumers were urged to return recalled kits to a pharmacy for an exchange or a refund.

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Your GP can give you a blood pregnancy test as early as 11–14 days after ovulation and it is recommended that women confirm a positive pregnancy test with their doctor.

"Blood test results are about 99 per cent accurate and can detect lower amounts of hCG than urine pregnancy tests," says the Better Health Channel website.

However, Dr Jessup says if you are trying for a baby, it is best to see a fertility specialist.

"I have seen so much incorrect information given out by GPs. One woman was told by several GPs that she didn't have a problem and should just keep trying naturally," said Dr Jessup.

"She was 39 when she first approached a GP for fertility advice and eventually came to see me by the age of 47, by which time it is too late for her to have a baby using her own eggs. A devastating result for her."

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