Using burnouts to announce the gender of a baby has become popular across social media.
Videos show prospective parents fitting out cars with tyres designed to smoke a specific colour when a burnout is performed - pink for a girl and blue for a boy.
Australian media has discovered the new techinque, with Sunrise questioning the "excessive" practice and presenters labelling it as "cringe-worthy".
News.com.au called it gender reveals "taken to a new potentially dangerous level".
One Sydney company may have been behind some of the burnout reveals, posting videos on social media.
Sydney Event Escorts reportedly posted two videos of burnout gender reveals on its Facebook page, but when contacted by News.com.au, it denied taking part in the reveals.
"We just filmed it because they're neighbours... I don't know them," said an employee, known only as Sam.
The videos have since been removed from the Facebook page.
In New Zealand, performing burnouts in public places is illegal as it involves a sustained loss of traction on the road.
A police spokesperson told Fairfax: "The maximum penalty for this offence is three months imprisonment and minimum disqualification for six months, or a $4500 fine and minimum disqualification for six months."