New data suggests hundreds of Australian couples are travelling overseas to undergo IVF treatment that allows them to select the gender of their child.

A new study found around 120 couples attended a single IVF unit in Thailand over an 18-month period, to avoid Australia's regulatory ban on social sex selection.

Australian medical guidelines currently prohibit parents from picking their child's sex unless there is a risk of the child suffering a serious genetic condition.

Medical director of Genea IVF clinic, Associate Professor Mark Bowman, says the couples travelling overseas are making informed decisions.

"The vast majority of these people just happen to be ordinary Australian couples who have had perhaps two children of one gender and desire to have a child of another gender," he said.

"They've done their research online and they've recognised that this is a way that technology can achieve that."

Professor Bowman says couples are paying between $8000 and $20,000 to choose their baby's sex.

He says the regulatory ban is not preventing people from seeking out treatment and many medical experts believe the ban should be reconsidered.

"Many fertility specialists in Australia believe that under the right circumstances and with the right counselling, it probably is a treatment that should be offered in Australia," he said.