Chandler Bush says freezing her eggs has given her "peace of mind".
The 30-year-old from Victoria has endometriosis, and is concerned it may impact her fertility.
It is often reported that 30 to 50 per cent of women with endometriosis experience infertility, but some experts say higher quality research finds it to be about 10 to 15 per cent.
"I would say it is a little bit of an insurance policy for me. However, I am quite aware there are no guarantees with egg freezing," Chandler told ABC Radio National.
"I would like to use my eggs within the next two to three years, depending on things like housing stability and my career and my relationship."
Egg freezing, formally known as oocyte cryopreservation, is often sold by fertility clinics as an "insurance policy". But senior research fellow with Monash University Karin Hammarberg says it's more like a lottery.
"An insurance policy implies that you put stuff away and go back and use it [at some point] and it will give you an outcome that you want — but that is just not [always] the case."
And research shows few women end up using their frozen eggs, and of those who do, only some result in a live birth.
The process of egg freezing
After having an anti-Müllerian hormone (AMH) test — the controversial 'egg timer' test experts say does not measure fertility — through her gynaecologist, Chandler was referred to a fertility specialist and began the process of "injections, scans, blood tests" and then finally, egg retrieval.
It's about a two-week process, and the eggs are surgically removed under sedation, explains Charley Zheng, a fertility specialist and obstetrician with private clinic Adora Fertility.
Dr Zheng says a treatment cycle typically costs between $5,000 to $10,000, and some women will need to undergo two to three cycles to achieve the desired number of eggs.
Subsidies are available for women with medical indications, he says.
Ongoing storage costs about $500 each year.
Why women choose to freeze their eggs
The literature shows the largest group of women who choose to freeze their eggs are those who don't have a partner, says Dr Hammarberg, who has 20 years' experience as a clinical coordinator of IVF programs.
"Or they have a partner and he's not willing to commit to parenthood — he's not ready.
"That's why I always want to [have a go at men] to learn about fertility and what is actually biologically possible. It's not just a matter of 'leave it for later, it will be fine'."
Dr Hammarberg says anecdotal evidence sometimes indicates women are freezing eggs to buy themselves more time to establish career or experience travel, "but that's the minority".
"It is really driven by the fact that women know they want to have children, are worried about fertility because they understand it gets less likely with age, and have a fear of missing out."
She says some single women say freezing eggs takes the pressure off when dating.
"They say, 'I don't want to feel like every date I go on I'm trying to work out straight away if they want to have children.'"
There is a smaller group of women who may need medical treatments that could compromise their fertility in some way, who are advised to freeze their eggs, explains Dr Zheng.
How many women return to use their frozen eggs?
There are different statistics out there on how many women return to use their frozen eggs, and generally range from 6 to 20 per cent.
For example, a 2021 study found a return rate of 7.4 per cent, and a review from earlier this year found it to be 11.1 per cent.
Analysis of eggs stored at Monash IVF clinics in Victoria between 2012 and 2021 shows fewer than 13 per cent of patients returned to use their eggs each year.
Dr Hammarberg says the main reason women don't come back to use their frozen eggs is because they conceive naturally.
"The younger you are when you freeze your eggs, the less likely you are to come back to them."
Research also shows of those who have frozen eggs and return to clinic to attempt pregnancy, more than half instead use fresh eggs via intrauterine insemination (IUI) or in vitro fertilization (IVF).
The data on how many women go on to have live births as a result of using their frozen eggs also varies, but sits between one in five and one in three.
The younger the woman was when she froze her eggs, the more likely she will have a live birth, says Dr Hammarberg.
Controversial marketing
Marketing around egg freezing from fertility clinics is a concern for Dr Hammarberg.
"Some use the language: 'Gives you the flexibility to start a family when the time is right for you' and 'We can store your eggs so they are ready whenever you are'.
"That implies this is a guarantee."
Dr Hammarberg says there is also growing concern around the use of influencers to promote healthcare services including egg freezing.
"We are in a bit of dangerous territory I think in terms of how informed the actual decision-making is."
Given an increasing number of women in Australia are choosing to freeze their eggs, Dr Hammarberg says it's important women have the facts to make an informed decision.
"I'm not saying people shouldn't do it, but please, get clear on the numbers.
"Everyone can make a good decision for themselves with detailed and personalised information."
This is general information only. For detailed personal advice, you should see a qualified medical practitioner who knows your medical history.
