An "alarming" number of Australians are playing Russian roulette with their fertility because of a common misunderstanding of the impact that a woman's age has on egg production, experts warn.
- Research finds that Australians underestimate the impact age has on fertility
- Experts says the average age of women having children is approaching 31
- Research also finds many are unaware of a simple test which can detect egg reduction
Flinders University researchers released a paper which found both women and men "consistently underestimated natural and IVF-assisted fertility with increasing age".
Professor Kelton Tremellen co-authored the paper and said the findings were "alarming".
"There's been a trend over the last four decades of people leaving it later in life to start a family and currently it's approaching about 31 years of age that women are having children," he said.
He said people tend to hold off falling pregnant to fulfil career and education goals but without testing to see if they are prone to premature ageing of the ovaries.
"That's a bit of a concern because fertility declines with increasing age and we know that about 10 per cent of the population will pretty well run out of good quality eggs by their mid-thirties and are at real risk of not being able to have kids at all," he said.
Professor Tremellen said the research also found many Australians were unaware of a test known as Ovarian Reserve Screening, which can detect if a woman's egg production has reduced.
He said that condition has very few symptoms.
"They just don't know about it. They don't have any symptoms and they're totally unaware," he said.
The test is done by taking a blood sample and measures hormone levels.
"Anti-Müllerian hormone is made by the developing eggs and as you get older and you decline in the number of eggs the hormone level drops so it gives us an idea in what the individual's egg count is," he said.
Professor Tremellen said women who are planning on having children in their thirties should take the Ovarian Reserve Screening tests from age 28.
"It costs between $90 and $100," he said.
"It's not a perfect test but it's the best non-invasive test we have.
"If a lady had a result at 28 that was more like a 40-year-old's result then I would be saying 'look, I really think you need to consider bringing forward your plans to have kids because that will give you a better chance of success'."
Freezing your eggs 'not ideal'
Professor Tremellen said women who have low egg reserves can freeze their eggs but it's not "ideal" for a number of reasons.
"I always get concerned about freezing eggs because we don't know what the quality of those eggs are until we thaw them," he said.
"So you don't know what sort of insurance policy you have when you do freeze."
"The pregnancy rate for frozen eggs is probably on five per cent per egg, so you really need to freeze probably 20 eggs to get a decent chance of success.
He said it was also an expensive option.
"It's not covered by Medicare so the patient has to pay for that themselves and that's expensive," he said.