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SPECIAL REPORT: Should you freeze your eggs?

I’m standing in a laboratory, dressed in scrubs – right down to pink shoe covers and an attractive green paper shower cap.

In front of me sits a row of rather unremarkable looking containers that look like barbecue gas bottles. They’re actually cryostorage containers – within them lie dozens of frozen embryos. I feel goosebumps rise on my arms as I realise I’m standing in the presence of potential human life.

This is the engine room of IVF Australia, one of the world’s leading fertility clinics, located just near Sydney’s Westmead Hospital. The scientists here are at the cutting edge of some of the most exciting fertility breakthroughs seen, and this humble WH-er – standing slack-jawed and wide-eyed in my sexy green cap – has been sent to meet them, and to find out about a new egg freezing technique called vitrification.

Sure, egg freezing is nothing new – the first baby born from a frozen egg happened a quarter of a century ago. But while other fertility technologies like IVF have enjoyed ever-increasing success rates, egg freezing has remained the awkward underachiever, with pregnancy rates dwindling at dismally low levels. The problem lay in the freezing itself, which took several hours, allowing ice crystals to build up, damaging the fragile genetic material contained in the egg.

But everything started to change around 10 years ago, when scientists began experimenting with vitrification, a flash-freezing technology. This new method seals an egg in ice in seconds, leaving no time for crystals to bloom (think snap-frozen peas, just slightly less suitable as a side dish). Now, experts are reporting pregnancy rates using eggs frozen via vitrification that are comparable to IVF with fresh embryos.

Researchers from the Cryobiology Unit at Institut Universitari IVI Valenicia in Spain carried out a randomised trial involving 600 recipients of either freshly harvested eggs or those preserved via vitrification, and found that the pregnancy rate among women who received the vitrified eggs was 43.7 per cent, as opposed to 41.7 per cent in the freshly harvested egg group. So is this the answer for women who are facing declining fertility, no decent bloke in sight and the deafening tick of their biological clock – freeze now, breed later?


The incredible egg

Everything you never knew about this ova-tion sensation
It’s the largest cell in the body, yet the average egg is 10 times smaller than the full-stop at the end of this sentence.

- Every egg in your body is fully formed before you’re even born. The growth took place during your 10- to 20-week gestation period.

- Your body begins to prepare an egg for fertilisation 3 to 4 months before ovulation.

- Healthy eggs are smooth and spherical. If one or more of your eggs is oblong or develops vacuoles (mini moonlike craters), it could signal problems.

- Your eggs follow a strict path of order: the first egg created by your body when you were a foetus was the first egg that dropped during your first period. And so on...

- The average woman ovulates about 450 eggs in her lifetime; the leftovers just disintegrate.

- Yes, a woman’s egg has a yolk. It’s packed with proteins that nourish the embryo during the first three days.

- Eggs are monogamous – they’ll let in only one sperm. And then the zona – the egg’s coating – permanently mutates to make sure no other swimmers get in.

- A week after fertilisation, the embryo has already grown to the size of a pinhead. After five weeks, it’s the size of a grain of rice.

- The oldest frozen egg to yield a healthy baby had been on ice for 25 years. Brrrr.

Not quite, says IVF Australia’s medical director Associate Professor Peter Illingworth, who has more than 20 years specialist experience in infertility practice. He’s just returned from performing an embryo transfer, and is still in his scrubs. But he’s eager to sit down for a chat.

“It’s not that simple. It’s right for some women, but it isn’t an amazing answer. Let’s say you’re 36, and Mr Right is nowhere to be seen. How does egg-freezing stack up for you? Well to begin with, the experts who’ve done a lot of egg freezing in US and Spain all generally agree that the effect of freezing and thawing an egg makes it about four or five years older – so that would be like an egg that’s come from a 40 year-old woman.” And the older the egg, the lower the chance of a successful pregnancy.

Also, most women will only have one batch of eggs frozen (the entire process is like the beginning of an IVF cycle: it involves two weeks of hormone injections to stimulate the growth of eggs, followed by 15 minutes under general anaesthetic while the mature eggs are collected). According to Professor Illingworth, this will probably net you a harvest of about 10 eggs. Once they’ve been frozen and thawed, your chance of falling pregnant from one of these eggs is probably only about 25 to 30 per cent, compared to around 40 per cent if you were doing IVF using a fresh embryo.

“What’s critical is that when you’re doing regular IVF and it doesn’t work you can try again right away, and go through another cycle to get another batch of mature eggs the next month,” Professor Illingworth explains. “So if a couple in their mid-30s want to go through IVF, they have a very high chance of success – just probably not on the first go. When you bank your eggs from one cycle, you don’t know what will happen. You can’t say ‘I’ve banked my eggs. I’m OK now, I can relax’.”


READ MORE: IVF FAQS

Because this technology is so new here, it’s also hard to properly gauge its potential success rates.

“None of us in Australia have very much experience with the thawing of eggs yet,” Professor Illingworth says. “Very few women have come back to use their frozen eggs over the past few years. So we don’t know how well any lab in Australia will thaw them, or what success rates are.

“But if you understand all of these possible limitations, and have the money (it costs around $12,000, plus $500 for each additional year they remain frozen) and want to spend it on putting your eggs away we’ll do it. It’s a very straightforward procedure – but beware, there’s only a chance that this could help you.”

This chance is one that Katrina – a 40-year-old mother of one and part-time health worker from Brisbane – wants to take. She’s about to have her eggs frozen, and she’s tired of being told “beware”.

“Every woman my age knows where our fertility is at,” she says. “I don’t need to be reminded that this procedure might not work and that I may not have any more babies.

“Also, after leaving a violent relationship, I have some trust issues that are preventing me from finding a partner. My husband stole so much from me, and my decision to freeze eggs feels like I am regaining my power – that I am the one making the decisions, I’m not victim to someone else’s choices.” Right on.

TIP OF THE ICEBERG

Egg freezing is not the only technology taking centre stage in the baby-making world – scientists at IVF Australia are working with other new methods that are radically increasing couples’ chances of pregnancy.

“I doubt that we’ll ever reach the point of 100 per cent success rates,” Professor Illingworth says. “That’s because we’re up against the limiting factor of the genetic material we have to work with. You see, every woman and man makes good eggs and bad eggs; good sperm and bad sperm – the lottery is, when we get eight or nine eggs from a woman, how many of those eggs will have the right genetic material inside of them?”

Previously, fertility scientists were only able to look at whole chromosomes to see if an embryo was potentially going to result in a successful pregnancy.

“All we could do was attach a coloured dye to a few key chromosomes,” Professor Illingworth says. (This technique is known as Fluorescence in-situ Hybridisation, or FISH.) “The dye would make the chromosomes light up, so we could see if there were any extras or any missing. But that was all we could see. And so we could go through the stages of making an embryo and it could look like the most beautiful embryo in the world when we transferred it, but because there was a problem we couldn’t see it just wouldn’t work.”


A guide to giving

- It’s illegal to sell sperm or eggs in Australia and NZ, but you can donate. Clinics like IVF Australia get a significant number of men coming forward to donate; around two-thirds will go ahead. First they have to undergo counselling and semen analysis. Then there’s the law – all sperm donors have to consent to being listed on a donor register, and once any kids born from your sperm turn 18, they can find out who you are.

- While it’s physically easy for a man to donate sperm (hello, Playboy), it’s not so easy
for a woman. Egg donors tend to be different – women usually won’t come forward to donate to an organisation, but they will come forward to help a friend or family member.

- That’s because donating eggs requires a woman to undergo the whole IVF process of injections and egg collecting under anaesthetic. That’s a lot more taxing than a quick date with Mrs Palmer and her five daughters.

- Because of this, fertility clinics can’t meet demand for donated eggs.

Now, new technology is allowing doctors to look at an egg’s genetic material in detail. After using a laser to drill a miniscule hole and slice off a cell from a three day-old embryo, scientists can now look at that cell and see every chromosome, all the way down a great big long string of genetic material – even fragments of the chromosome. This means that they can now identify even partial chromosomal abnormality. (With FISH, 40 per cent of chromosomes with partial abnormality would have been given the all clear.) And that means they can choose a couple’s best embryo for transfer.

But there’s more. In the past, it would take up to three weeks for any complex genetic testing, meaning embryos would have to be frozen and transferred later. With this new Advanced Embryo Testing technology – which is literally only months old – this can be done in 24 hours, meaning the entire process can be completed in one IVF cycle using a fresh embryo transfer.

So why isn’t everyone doing this for every couple needing IVF? “The drawback is, the microchips needed for the 24-hour analyses are still very expensive,” Professor Illingworth says. “The chips contain 5000-plus gene sequences – it’s incredibly sophisticated. Right now it’s an extra $3000 on top of IVF costs, so we only use this on women who’ve had multiple miscarriages and IVF rounds.”

This technology doesn’t just help choose the best embryo for the best chances of a pregnancy. It can also save people a lot of false hope and grief: “We had one patient who had six embryos – all with abnormalities,” says Professor Illingworth. “While this was a disappointing result, the patient said to us, ‘you’ve saved me six miscarriages’. Not to mention additional IVF cycles. She’s looking at other options now – and may have a potential egg donor.”


COUNTING YOUR CHICKENS

A woman is born with two million eggs. By the time she’s 45, that number will have dropped to about 1000.

“In the average woman’s ovaries there are three different types of eggs,” explains Professor Illingworth. “There’s the tiny undeveloped eggs; the growing eggs and normally maybe one mature egg ready to be released.

In the past we could do ultrasounds and count the larger ones, but until recently there was no way to know what kind of pool of undeveloped eggs there was in there.”

Enter AMH – a blood test that detects Anti Mullerian Hormone, secreted by early ovarian follicles. By measuring levels of AMH in a woman’s blood, scientists can predict a woman’s egg reserve. And at a mere $65 a pop and a trip to your GP, it’s an inexpensive way to find out where you stand. In a nutshell: the more AMH present, the greater the number of eggs remaining. But are they good eggs?

“That’s the dilemma,” Professor Illingworth says. “A woman at 35 may come to us for egg freezing, and if she takes this test and has a good supply of eggs left she may decide to hold off. But AMH tells us nothing about egg quality – only that women’s potential future fertility.”

Still, it’s enough to help ascertain if a 41-year-old woman could be a viable IVF candidate, or if a 33-year-old should start looking for alternatives. So, while grey areas still exist, things are a looking a lot more clear cut.


LIFE AS WE KNOW IT

While these new technologies are incredible, I can’t help but stop and ask the question: are scientists just messing with Mother Nature? Are they playing God?

“This is not eugenics,” Professor Illingworth points out. “We can’t pick the blonde-haired, blue-eyed babies. We’re just helping to overcome the anomalies that will stop a pregnancy in the first place.

“Sure, you can say that maybe people aren’t supposed to be passing on their genetic material for a reason, but when you’re dealing with – say a Muslim couple who’ve been ostracised by their family because they can’t have children – do you say to them, ‘well no, there’s a possibility we could be passing on your bad genetic material to future generations’? Of course not.”

While it’s too soon to know if babies born via these technologies will be affected in the future (the first people born via IVF are just reaching their 30s now) it is known that babies born via IVF have a slightly higher risk of health problems than babies conceived naturally, although this is only a matter of a few percentage points.

“We don’t know why this is,” the professor says.

“But we’re certainly not damaging or destroying our gene pool – the proportion of couples who conceive through IVF is still only three per cent. And the impact that this all has on the individual is fantastic.”

As I leave the clinic, I find myself thinking about how truly miraculous conception, pregnancy and birth actually are – how every child conceived naturally really is a one-in-a-million occurrence, including me. Way to feel special, eh?

The fact that there are now methods to help people who are struggling to make that one-in-a-million human life on their own is something to be in awe of. What’s more, it’s giving us women more choices and more freedom in our lives. And when you consider how far fertility technology has come in such a short amount of time, the mind can only boggle at what we can expect in the future. Stay tuned, baby.