A LEADING social demographer says the introduction of the baby bonus in 2002 was a key factor in arresting Australia's declining fertility rate.
McCrindle Research principal Mark McCrindle said Australia's fertility rate "turned the corner" in 2002 after four decades of decline.
Australia's fertility rate - the number of babies per woman - was 3.5 in 1965.
By 2001 that number had dropped to 1.73 and was tipped to go as low as 1.5.
But in 2002 Treasurer Peter Costello introduced the baby bonus, and in doing so offered the famous advice that women should have "one for the father, one for the mother and one for the country".
Figures released by the Australian Bureau of Statistics on Thursday - three days after the Federal Government announced changes to the baby bonus - showed the national fertility rate in 2011 was 1.88.
"You'd have to say the two (the baby bonus and rising fertility rates) are linked," Mr McCrindle told APN Newsdesk.
"But I don't think it's purely the economic incentive of the baby bonus. I think in addition to that it started a national conversation.
"Prior to that point there was a lot of talk in the '90s and into the 2000s of over-population and the benefit of smaller families.
"But Peter Costello, in encouraging births, gave a social validation to families of three or more."
The ABS figures - contained in the publication Births, Australia, 2011 - showed the number of babies born in Australia last year topped 300,000 for the first time.
More than 301,000 little Aussies were born in 2011, almost 4000 more than the previous year and 55,000 more than a decade earlier.
It was also revealed the number of women over the age of 30 having babies has been steadily increasing over the past decade.
More than 164,000 babies were born to women 30 years and older in 2011, up more than 40,000 on 2001.
There was also a record number of women over the age of 40 who had babies last year.
More than 12,800 babies were born to women over the age of 40, compared to more than 7100 in 2001.
The fertility rate for women in the 40-44 years category jumped from 9.2 babies per 1000 women in 2001, to 15.1 last year.
There were also substantial rises in the fertility rate for women in the 30-34 (from 107.9 to 122.4) and 35-39 (49 to 69.6) age groups.
Mr McCrindle said women were having babies later in life due to a combination of social, economic, educational and biological factors.
He said the "markers of adulthood" were being pushed back as people stayed at home and in education longer.
"The markers of independence which were marked by marriage, mortgage, children and getting into a career, all of that has been pushed back," he said.
He said people were also more aware of the cost involved with raising children.
Advances in science had also made it easier for older women to have children, he said.
"Some of the births as mums get older would be through assisted fertility," he said.
"That is becoming more available and more prominent."
- Almost 100,000 babies born in NSW last year, the most in a decade.
- The NSW fertility rate was 1.908 babies per woman.
- More than 63,000 babies born in Qld last year, 15,000 more than a decade earlier but less than the previous two years.
- Queensland's fertility rate sat at 1.964 babies per woman in 2011.
- Tasmania had the highest fertility rate at 2.17 babies per woman.
- Victoria had the lowest fertility rate at 1.75.
- The median age for mothers was 30.6 years in 2011, a rise of 0.6 since 2001, and 33 for men.
- The average time married people waited to have a child dropped from 4.5 years in 2001 to 4 years in 2011.
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