MEN are being blamed for many cases of Sex and the City-style career women who delay having children into their 30s.

Women say not finding Mr Right, having a partner who will not commit to the relationship or having children, lack of cash, education debts and housing costs are key reasons for deferring parenthood, the Herald Sun reported.

The research has prompted calls for more support for wannabe mums and the role to be valued.

One potential mother, Narelle Craig, 30, said she did not meet the right man in her 20s and had focused on travel and work.

Ms Craig, a partner in an apparel and merchandise company, said she did not want to rush into starting a family until "all the boxes were ticked".

She has embarked on a new relationship, but the topic of children has not yet arisen.

"It's not about being career-obsessed, historically I haven't been with the right man," she said.

"Most girls want to have children, but meeting the right person is something you can't control."

A study published this month in the Journal of Population Health found most women aged between 30 and 34 want to have children, but could not for reasons often out of their control. It dispelled the image of hordes of "selfish" women deferring children for their careers.

Only 20 of the 569 Australian women surveyed by Jean Hailes for Women's Health researchers said they did not want to have any children.

The report said much of the public debate around Australia's fertility rate blamed women deliberately choosing not to have children.

But one of the authors, Dr Sara Holton, said the study highlighted the issue was far more complex.

"This blows away the assumption that it's a voluntary thing for women, that they can choose when and how many children they have," she said.

Women need more support to have children and men should be educated on the impact of age on fertility, she said.

Victorian Women's Trust executive director Mary Crooks said motherhood was not valued in society as much as it should be.

"We are in love with the idea of motherhood in our country, but unintentionally and ironically, we don't do a lot to support it, and drag it down as an ideal," she said.