the chance of giving birth to a healthy baby
Tuesday, October 26, 2010
An IVF test that trebles a woman’s chance of having a baby has been developed by scientists.
It could spare thousands of couples the heartache of miscarriage as well as removing the risk that children conceived by fertility treatment have of conditions such as Down’s syndrome.
It also offers hope to those undergoing fertility treatment in their late 30s and early 40s, who often struggle to get pregnant and, once they do, are more likely to lose the baby.
The test developed by American researchers is called Chromosome Aneuploidy Screening, has been so successful that experts believe it will be routinely available to women undergoing IVF in private clinics or on the NHS within the next three years.
The screening checks embryos for chromosome abnormalities. Any which are faulty are discarded, and only those which stand the best chance of developing into a healthy foetus are implanted back into the womb.
Trials have shown that up to 88 per cent of women receiving tested embryos give birth.
This is more than treble the success rate of IVF – only between 20 and 30 per cent of those undergoing treatment in Britain will have a baby.
The test, which was unveiled at the American Society for Reproductive Medicine conference in Denver, Colorado, costs £2,000 a time, on top of the normal price of IVF of around £4,000.
But its success rate means that couples paying for private treatment would potentially save thousands of pounds as they would probably need only one cycle.
It would also cut millions from the NHS’s fertility treatment bill. Couples are normally offered up to three free cycles of IVF at a total cost to the health service of 12,000.
Last year British scientists unveiled a similar screening technique that also used chromosome screening to select only the healthiest embryos for IVF.
But this latest method is at a far more advanced stage and has been subject to rigorous testing, unlike the British technique.
For this reason it is likely to be the first IVF screening method to be available in British clinics, and researchers believe it will be widely used within two or three years.
Tony Rutherford, chairman of the British Fertility Society, said: ‘It’s technically challenging but if held up in future research it is something we’d clearly like to see introduced in helping to select the best embryos to be transferred.’
Normally during IVF, up to 24 eggs are taken from a woman’s ovaries to be fertilised with her partner’s sperm. Doctors then look at the shape and size of the embryos and choose what they think are the healthiest ones to be implanted.
But experts say this current method is very unreliable at picking up faulty embryos.
In addition, many IVF clinics will implant two or three embryos to try and boost a woman’s chances of having a baby. Often more than one will develop into a foetus meaning she will have twins or triplets, which involves extra risks to the babies.
The new technique involves taking a sample from embryos when they are five days old and checking each of its 23 pairs of chromosomes. Only the healthiest single embryo is implanted in the womb.