Children of same-sex parents enjoy better levels of health and wellbeing than their peers from traditional family units, new Australian research suggests.

In what they described as the largest study of its type in the world, University of Melbourne researchers surveyed 315 same-sex parents and 500 children about their physical health and social wellbeing.

Lead researcher Doctor Simon Crouch said children raised by same-sex partners scored an average of 6 per cent higher than the general population on measures of general health and family cohesion.

"That's really a measure that looks at how well families get along, and it seems that same-sex-parent families and the children in them are getting along well, and this has positive impacts on child health," Dr Crouch said.

There were more than 33,000 families with same-sex parents living in Australia, according to the most recent Australian Bureau of Statistics census.

Lack of gender stereotyping in parenting roles promotes harmony

Dr Crouch said same-sex couples faced less pressure to fulfil traditional gender roles, which led to a more harmonious households.

"Previous research has suggested that parenting roles and work roles, and home roles within same-sex parenting families are more equitably distributed when compared to heterosexual families," he said.

"So what this means is that people take on roles that are suited to their skill sets rather than falling into those gender stereotypes, which is mum staying home and looking after the kids and dad going out to earn money.

"What this leads to is a more harmonious family unit and therefore feeding on to better health and wellbeing."

Rodney Chiang-Cruise, a parent raising three boys with his same-sex partner, agreed with the study's findings.

"The traditional nurturing role is shared - it's not one parent over another; the traditional breadwinning role is shared," Mr Chiang-Cruise said.

"My personal view is that I think it teaches the child that everyone contributes in an equal way and you all have to contribute to the family."

Dr Crouch said the study findings had implications for those who argued against marriage equality for the sake of children.

"Quite often, people talk about marriage equality in the context of family and that marriage is necessary to raise children in the right environment, and that you need a mother and a father to be able to do that, and therefore marriage should be restricted to male and female couples," Dr Crouch said.

"I think what the study suggests in that context is that actually children can be brought up in many different family contexts, and it shouldn't be a barrier to marriage equality."

'No surprise' same-sex parents claim success: Family Voice

Family Voice Australia research officer Roslyn Phillips said the study should be taken with caution.

"I wasn't surprised that these parents who volunteered for the study all thought their children were doing well," Ms Phillips said.

"You've got to look beyond studies like these to what happens when the child reaches adulthood, and that's the only time with independent assessment you can really say what's gone on with the parenting and then ask them how they're going in all sorts

of ways, I think that would be a more relevant study.

Ms Phillips also questioned the the objectivity of the study's lead researcher.

"Simon Crouch is raising two young children himself with his male homosexual partner, the results should be taken with caution," she said.

However, Dr Crouch said his personal situation did not impact on the results of the study.

"I acknowledge that I am from a same-sex-parent family, however I am one of a number of researchers on the paper who come from all sorts of different backgrounds," he said.

"There's a wide range of research across many different areas; first and foremost I'm a researcher, I'm a medical doctor and I'm a public health practitioner, and the objectivity I bring to this study doesn't depend on my own personal situation."

Mr Chiang-Cruise said Family Voice Australia's concerns did not reflect the majority of society.

"Very small radicalised minorities have a very large voice," he said.

"The only thing we can do is to make sure our kids are resilient and understand that their families are great, they work just as well."

Dr Crouch said a broader project was currently in the works where children of same-sex couples between the ages of 10 and 18 had reported on their own health outcomes.

Stigmatisation still a problem for same-sex-parent families

Dr Crouch said that despite scoring better in general health and wellbeing, same-sex-parent families regularly dealt with social stigma.

"Within these families, stigma is a problem and stigma is experienced in many ways within society," he said.

"For these families it might be something as simple as a letter coming home from school addressed to Mr and Mrs, which wouldn't be appropriate for these families, but it can be more overt and damaging such as bullying in the playground.

"We also see a lot of negative rhetoric spoken about same-sex parent families and this has a negative impact on child health in this context."

Mr Chiang-Cruise said such stigmatisation was a challenge for him as a same-sex parent.

"We have the same problems as every other family - we have kids who don't want to do their homework and don't want to eat their dinner and all that sort of stuff," he said.

"We are no different in that regard; we just have to work a little bit harder to make our kids more resilient."