There’s no doubt that fertility wanes dramatically after the age of 35 and, beyond 40, the chance of a woman getting pregnant using her own eggs is about three in ten.
But the reality of egg-freezing is a long way from the hype. The chances of conceiving a baby from a frozen egg are low, and freezing itself is a painful, costly process involving potent fertility drugs, chemicals and surgery.
A recent report by the American Society of Reproductive Medicine (ASRM) declared that egg-freezing is no longer the experimental technology it once was, and has even recommended that women freeze their eggs in their 20s and 30s as a routine insurance policy for conceiving babies later in life.
Astonishingly, American egg-freezing facilities now hard-sell ‘fertility preservation’ to the parents of single 30-something women who pay for egg-freezing cycles for their daughters to increase their chances of having grandchildren.
Just under 6,500 eggs have been stored in Britain in the decade since egg-freezing was FIRST licensed by the Human Fertilisation and Embryology Authority (HFEA).
Many eggs are harvested from women whose fertility has been impaired by cancer treatment, but increasing numbers are stored for women like Julia who haven’t yet met the right man, or are waiting until later in life to start a family.
Egg freezing is funded by the NHS if carried out for women having cancer treatment. Otherwise it costs around £5,000 per cycle, then £200 a year to pay for safe storage of the eggs.
If a woman chooses to thaw her eggs, an IVF procedure called Intracytoplasmic Sperm Injection (ICSI) is used to insert a single sperm into the egg, at an additional cost of £2,000.
But delaying having children by egg-freezing is no guarantee against infertility, and there are fears that women might be lulled into a false sense of security about their future chances of having a family.
‘Saying something is no longer experimental is a far cry from saying it’s going to work,’ says Professor Robert Harrison, a consultant gynaecologist and obstetrician, former president of the International Federation of Fertility Societies (IFFS), and author of The Smart Guide to Infertility (Hammersmith Press £14.99).
‘Women who are fertile and freeze their eggs to delay having a child could be putting themselves through pain, risk and expense, and be unlikely to get a baby at the end of it.’
Ten years ago, when the first baby was born from a frozen egg in the UK, it seemed technology had finally delivered the ultimate blow to the biological clock.
Since then, however, only 12 babies have been born from frozen eggs in this country.
Professor Harrison says: ‘We don’t have enough babies born in Britain from thawed eggs to know for certain whether egg-freezing is effective or safe in terms of the long-term health of children.’
Last October, a poll of 3,000 British women by Red magazine found that one in five aged 28-45 would consider egg-freezing. The number of women who froze their eggs in Britain has increased five-fold in the last decade.
Yet the cruel biological reality is that by the time most women consider egg-freezing, it’s already too late.
‘I get many calls from women around the age of 38 who want their eggs frozen,’ says Dr Gillian Lockwood, medical director of Midlands Fertility Services, where 207 women have had their eggs frozen, and where 50 per cent of British babies born from frozen eggs have been conceived.
‘A frozen egg from a 38-year-old will be better than a fresh one from a 42-year-old, but pregnancy is still not very likely,’ Dr Lockwood adds.
Professor Bill Ledger, former president of the British Fertility Society and professor of reproductive medicine at the University of New South Wales, Australia, says most experts discourage women over 36 from freezing their eggs because the odds are against them conceiving.
He explains: ‘Biologically speaking, the ideal age for a woman to start thinking about freezing her eggs is 30. Then she has a 50/50 chance of having at least one baby later.’
The chance of a woman who freezes her eggs at 40 having a baby from one of those eggs is only 10 per cent. ‘We could end up with a generation of disappointed women who put faith in a process that probably won’t give them a baby,’ Professor Ledger says.
Even freezing one’s eggs at 30 could have its downsides, according to Dr Lockwood.
Until recently, eggs were frozen using ‘slow-freeze’ technology. But in 2008, a new process called vitrification or ‘flash-freezing’ – which chills the eggs in a fraction of a second – was licensed in the UK.
‘Early evidence shows eggs frozen by vitrification may work as well as fresh eggs, in terms of the chances of achieving pregnancy,’ says Professor Ledger.
However, there are concerns that the freezing and thawing process may damage egg quality.
The use of chemicals on the egg wall during flash-freezing could potentially damage the egg according to Dr Magdy Assaad, clinical director of the London Fertility Centre, where women can freeze their eggs up to the age of 44.
‘Only eight out of ten eggs survive the thawing process,’ he says. ‘Subsequently, the chances of getting a baby from a frozen egg are about one to three per cent for each egg.’
Professor Harrison says egg freezing may be risky for healthy women. In around five out of 100 cases, for example, ovaries over-react to fertility drugs, resulting in Ovarian Hyper Stimulation Syndrome (OHSS).
This is a condition where ovaries can swell to several times their normal size. Fluid may leak into the abdomen as a result and, in rare cases, cause internal bleeding, heart attack or death.
However, a new technique now used in some UK clinics and known as ‘Agonist Triggering’ uses milder hormones to stimulate egg production, which dramatically reduces the risk of a woman suffering from OHSS, Professor Ledger says.
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