IVF Study Finds Gene Defects in Eggs From Women of All Ages

By JENNY HOPE

EMBRYOS created in fertility clinics have far more genetic defects than previously thought, even if they involve eggs donated by younger women, experts warned yesterday.

The discovery has led specialists to suggest that all women having IVF treatment should have their embryos checked for conditions such as Down’s syndrome.

They say a new screening technique, currently offered only to older women in the UK, should be more widely available.

The results of the U.S. study contradicted the widely-held belief that the risk of genetic defects in eggs and embryos is higher for more mature women.

Researchers found that embryos from eggs donated by healthy young women had a ‘startlingly high’ level of genetic problems up to 42 per cent.

This could explain why so many IVF patients fail to get pregnant.

Experts now believe that defective eggs are common among women of all ages, but those which are fertilised naturally are rejected early on by the body.

There is also concern that drugs used in fertility treatments, to stimulate egg production, may add to the damage.

Fertility specialist Dr Jeffrey Nelson, who headed the study in California, said it involved 289 embryos created from eggs donated by 22 women under 30.

The eggs and embryos all looked normal but the screening technique, called Preimplantation Genetic Diagnosis, found that 42 per cent had chromosomal abnormalities.

PGD takes a single cell from an eight-cell embryo and screens it for genetic abnormalities, including Down’s. UK guidelines recommend that it is mostly used for infertile women over 35, where IVF treatment has failed, because the risks of genetic defects rises with age.

But Dr Nelson, managing partner of the Huntington Reproductive Center in Pasadena, said the UK policy was too inflexible.

He said: ‘If it was used more widely it would increase conception rates and reduce the number of embryos being transferred by selecting the healthiest embryo to use.’ The research was released yesterday at the annual meeting in Montreal of the American Society for Reproductive Medicine.

In a separate study, researchers using PGD found an ‘unexpectedly high’ rate of abnormal embryos among 36 women in their early 30s undergoing IVF.

Two-thirds were abnormal, compared with threequarters of those from women in their late 30s.

Dr Peter Nagy, scientific director of Atlanta-based Reproductive Biology Associates who carried out the study, said wider use of PGD would make a difference to pregnancy rates across all ages.

At present, eight clinics in the UK are licensed by the Human Fertility and Embryology Authority to provide PGD testing.

It is expensive, costing around Pounds 6,500 for an IVF cycle including PGD, but experts believe it is costeffective compared with looking after a child born handicapped.

It might even save money for childless couples because they would need fewer cycles.

Earlier this year, the Reproductive Genetics Institute in Chicago revealed that PGD increased the chances of a successful pregnancy from 11 per cent to 80 per cent.

The HFEA said last night: ‘Our expert group will monitor the development of this research and we will listen to the UK’s professional bodies if they feel other groups should be added to our guidance.

‘We are concerned that women are properly aware of the potential risks before they choose to have this test and that women and embryos are not tested unnecessarily.’