Most people who do not have kids have no regrets, but report significant social disapproval for not becoming parents, a study at Perth's Edith Cowan University has found.

Bronwyn Harman, a lecturer in the School of Psychology and Social Science, conducted an anonymous online survey of 559 Australians over 35 who do not have children and found a wide variety of experiences.

"There is childless and childfree. People who are childfree choose not to have children ever," Dr Harman told 720 ABC Perth.

"People who are childless are the ones who would love to have children but are unable to for a variety of reasons.

"One of the major things I found was that of the participants who were over 50 and chose not to have children, approximately one quarter said they regretted that decision.

"That's not comparable to other research that has been done in that area. Other research said that only about 2-3 per cent regret it."

Dr Harman said her findings were different because her study was totally anonymous and responses were completed online, freeing respondents to answer more honestly.

Of the 75 per cent of respondents who said they had no regrets, most could not give a reason as to why they did not become parents.

"Some decided they weren't maternal or paternal, some said children were too expensive, some said they actively disliked children," Dr Harman said.

"But the most common answer I got was that there was no reason — they just didn't think about having children or see it as an option for them."

Social pressure to settle down and have kids 'huge'

Dr Harman said the social pressure to have children in Australia was enormous, and many people reported pressure from family and friends.

"My study showed that women who choose not to have children get negative comments more than men but men still report negative comments as well," she said.

"Australia is one of the biggest pro-natal countries in the world.

"We believe the natural progression in life is to grow up, meet the right person, marry and have a child, that's what life is."

720 ABC Perth listener Karen, 27, said she was constantly hassled about her decision.

"I've had people say to me 'I guess you just hate kids'," she said.

"I work with children; I just don't want to take them home with me.

"I am constantly being told I'll regret it but I would rather regret not having kids than regret having them."

Karen is married and said her husband initially "had that idealistic view that you get married and have a family" but has now also decided he does not want to have children.

Caller Di said she had also faced a great deal of pressure when she was younger but also did not regret her decision.

"I'm at an age where most of my friends have grandchildren but I travel a lot with my partner which we were able to do because we don't have kids," she said.

"Children are fine for other people but I have just seen too many kids brought into the world that never should have been.

"I don't think everyone is born to be a parent and I certainly wasn't."

Parenting a lifetime commitment

Dr Harman said many of the people in her study reported strong relationships with nieces and nephews or friends' children.

"They just don't want to take them home," she said.

People who did regret not having children related that to feeling lonely.

"Many of them were single as well and they regretted not having family around them," Dr Harman said.

"They said they wouldn't have [anyone] to hand things down to, they had no reason to collect things.

"But regret can be a fleeting thing. When you are in your 50s or 60s or older, it is quite normal to look back at your life, whether you have children or not, and think about your life and perhaps other decisions you could have made."

Dr Harman said her message to people who were unsure about having children was "if you don't know, don't do it".

"Parenting is a really big commitment and it is a lifetime commitment," she said.

"People shouldn't feel pressured to conform to society's norms. Society shouldn't be pressuring people into having children anyway."