The number of IVF babies has been counted for the first time

We now know how many babies have been born via IVF, and that number is more than half of Australia's population.

There have been between 10 and 13 million IVF babies born in the 40 years since the first child was conceived via IVF in 1978, a world-first study has found.

However, the number of IVF births has soared in the six years since the study's cut-off period, Professor Georgina Chambers, one of the study's lead authors and director of UNSW's National Perinatal Epidemiology and Statistics Unit (NPESU), said.

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"We found IVF births have grown exponentially," Chambers said.

"Preliminary global data suggests an additional 3–4 million infants were born past the study's cutoff in 2018.

"This brings the total in 2024 to 13–17 million infants."

Chambers said Australia played a formative role in IVF's early history as the third country to successfully deliver an IVF baby in 1983.

Australia was also the first country to establish an IVF registry and data collected in Australia and New Zealand was among the most complete in the world, the professor said.

These days, one in every 16 babies born in Australia is conceived via IVF. For women aged over 35, that figure is closer to one in 10.

The study, published this month in Fertility and Sterility, is based on 1978–2018 data collected from fertility clinics and regional registries across the world by the International Committee Monitoring Assisted Reproductive Technologies (ICMART), of which Chambers is data custodian.

IVF is most popular in high-income countries such as Australia, where equitable access is supported by government funding and regulation.

"IVF is expensive and complex," Professor David Adamson, Chair of ICMART, said. "It requires skilled personnel, medications and high-tech labs. Without public funding or reimbursement, it's largely inaccessible in many parts of the world."

Reducing the number of multiple births

Multiple births used to be very common with IVF because clinics would transfer more than one embryo to try and improve the chance of pregnancy, Adamson said.

"With improvements in embryo freezing techniques, embryos can now be successfully transferred in subsequent cycles," he said.

"A single embryo transfer does not compromise overall success rates – and it is safer for mother and baby."

Australia has been a global leader in reducing multiple birth risk, Chambers said.

"Today, more than 93 per cent of IVF cycles involve a single embryo transfer, resulting in a multiple birth rate of below 3 per cent," she says.

"Most IVF babies in Australia now come from frozen embryos."