The ticking of the biological clock is an all-too familiar fact of life for many women. For those who want to start a family but haven't yet met the right partner, it can be a source of stress.
Egg freezing is often marketed as a convenient way to defy the march of time and ease the worry of dwindling fertility.
But what does it actually involve? Is it right for you? And does it really provide a safety net?
"It's not a guarantee," says Associate Professor Kate Stern, a fertility doctor from the Royal Women's Hospital and Melbourne IVF.
"Egg freezing can be a good option for some women, but the most important thing to remember is that, at most, this is going to give you a small additional opportunity in the future."
Prof Stern says women need to think about their "life plan", rather than rely on egg freezing.
"Particularly for older women, it might be better to just think about trying to have a baby now," she says.
Human oocyte cryopreservation – egg freezing – was originally designed as a fertility safeguard for cancer patients undergoing chemotherapy. However, advances in technology have increasingly led to it being offered as a way to buy women some time and reduce the risk of 'social infertility'.
By freezing eggs at a younger age, when they are better quality, women can retrieve them later in life when they are ready to start a family.
The advent in recent years of flash-freezing technology, called vitrification, has vastly improved the efficacy of the process. Up to 90% of eggs now survive the thawing process – up from around 20% when freezing was first developed – meaning the chance of producing a viable pregnancy is similar to that for fresh eggs.
Age plays a significant role in the success rate of egg freezing. Prof Stern says that for women under the age of 38, for every 15 to 20 eggs they freeze, there is still only a 50% chance of having a baby. Above that age, the chance of pregnancy drops significantly, as older women produce fewer eggs and the egg quality diminishes.
"Ideally, the best time to freeze eggs is between the ages of 26 and 33. But it is a very expensive process, which makes it difficult for a lot of women to access, and there is no guarantee of how many eggs you might retrieve", Prof Stern says.
Increased competition in the fertility market means prices vary, but one cycle of egg freezing can cost up to $8000, and it only attracts a Medicare rebate in some cases of medical infertility.
The process of egg freezing begins with ovarian reserve and function tests. These will determine the number and quality of eggs likely to be produced during a cycle.
Patients then give themselves hormone stimulation injections for two weeks before eggs are retrieved. Retrieval is done during a 15-minute ultrasound-guided procedure, under a light anaesthetic.
Eggs are frozen in liquid nitrogen and can be stored indefinitely. Under Victorian law there is a 10-year storage limit, but an extension can be sought after this time.
Prof Stern says women contemplating egg freezing need to ask for realistic advice on the number of eggs they will need to retrieve to have a reasonable chance of having a baby.
"For some women who do the tests and find their ovarian reserve is low, and their ovarian function is already a bit fragile, [they're] likely to only get three or five eggs and you have to ask, 'do I really want to do this?'," she says.
"Perhaps you should be thinking of having a baby on your own."
The procedure is relatively low risk, although there is a slight chance of bleeding and infection. A small proportion of women may have an adverse reaction to fertility drugs, resulting in ovarian hyperstimulation syndrome.
Dr Karin Hammarberg, fertility expert and author of IVF for Dummies, says the marketing around egg freezing was often "quite deceptive" and the procedure should not be sold as an insurance policy.
"It's actually more like a lottery that may or may not pay out," says Dr Hammarberg.
"For older women it doesn't really increase their chances of having a baby and for younger women they often never end up using the eggs because they will end up conceiving spontaneously."
Dr Hammarberg urges women to do their homework before freezing eggs, particularly around the financial implications, with some clinics now promising budget packages.
"There might be a low cost quoted, but you have to ask, does that include the hospital admission, the anaesthetist's costs, the fertility drugs or the cost of storage?," she says.
"Whatever cost is advertised, there are other costs that women need to consider."
Miranda* made the decision to freeze her eggs just before her 38th birthday. Miranda spent two years considering whether to freeze her eggs. "I was single and I always knew I wanted to be a mother," she says. "I thought I would have that typical family situation – meet someone, get married, have kids – and that hasn't happened." Miranda says the main barrier to freezing her eggs was the cost, "particularly as I thought I'd have to have multiple cycles because of my age." "But a friend said, 'It sounds like it comes down to what the value of having a child is to you.' It was the first time that I realised, that's what it comes down to – how much am I willing to spend if I really want a child?" Eighteen months ago, Miranda went ahead with an egg retrieval process. It cost almost $8000 and resulted in 13 eggs. "Ultimately I went ahead because I've always wanted to be a mother," she says. "I still hope to meet someone and do things the traditional way, but egg freezing gives me an extra option. "I know there's no guarantee that any of those eggs will be good quality or will result in a baby. I guess it just gives me a little bit of breathing space in terms of deciding what's next." *Not her real name.
Miranda* made the decision to freeze her eggs just before her 38th birthday. Miranda spent two years considering whether to freeze her eggs.
"I was single and I always knew I wanted to be a mother," she says.
"I thought I would have that typical family situation – meet someone, get married, have kids – and that hasn't happened."
Miranda says the main barrier to freezing her eggs was the cost, "particularly as I thought I'd have to have multiple cycles because of my age."
"But a friend said, 'It sounds like it comes down to what the value of having a child is to you.' It was the first time that I realised, that's what it comes down to – how much am I willing to spend if I really want a child?"
Eighteen months ago, Miranda went ahead with an egg retrieval process. It cost almost $8000 and resulted in 13 eggs.
"Ultimately I went ahead because I've always wanted to be a mother," she says.
"I still hope to meet someone and do things the traditional way, but egg freezing gives me an extra option.
"I know there's no guarantee that any of those eggs will be good quality or will result in a baby. I guess it just gives me a little bit of breathing space in terms of deciding what's next."
*Not her real name.
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