Scientists have developed a technique to use "super embryos" for older women, improving the likelihood of them having a healthy baby.
The technique could help thousands of women in their late thirties and early forties who have delayed having children and who are experiencing problems conceiving.
The findings, announced yesterday at the annual meeting of the European Society of Human Reproduction and Embryology in France, show that doctors can screen a single cell from an embryo before it is implanted in the woman to ensure it is high quality.
As women get older the risk of having an embryo with an abnormal number of chromosomes increases by up to 70-fold and can lead to malformations, early miscarriage and Down's syndrome. This is one of the main reasons that women over the age of 37 have lower rates of success with fertility treatment.
Researchers in Italy have developed the genetic screening tests. They have achieved the same pregnancy rate in women aged 38 to 44 as in a younger patient. "Women planning IVF or ICSI [types of fertility treatment] in the final part of their reproductive life can now enter treatment feeling their age is not a handicap anymore. This pre-implantation genetic screening test is able to overcome the natural reproductive failure that occurs due to the eggs ageing," said Dr Anna Ferraretti, clinical director of the Italian Society for the Study of Reproductive Medicine's unit in Bologna.
In the study, nearly 130 patients aged between 38 and 44 underwent the new test. These women had the same pregnancy rate, of 41 per cent, as 700 younger patients who underwent conventional fertility treatment. The miscarriage rate was only 4 per cent.
The study also included 182 women over 37 years of age who opted for conventional fertility treatment. This group only achieved a 25 per cent pregnancy rate, and were much more likely to miscarry, with 15 per cent losing their child.
The test is limited because only a single embryonic cell is used and the current error rate is 5 to 7 per cent. Older women who undergo the new test are also strongly recommended to undergo conventional pre-natal diagnosis to avoid the possibility of having an affected baby. "The social, psychological and ethical implications of the poor chance of a successful pregnancy among older women has become evident as more and more women over 37 years old ask for help from assisted reproductive technology. So to be able to offer these women the same chance of achieving healthy babies as younger women is now an important and heartening step forward," said Dr Ferraretti.
Over a quarter of women who go to fertility clinics are over 38 years old. On average they produce only seven eggs per cycle compared with 12 for younger women.
Nine out of 10 of the couples who took part in the study and had the new tests had a successful pregnancy after three treatment cycles.
The Italian researchers said that the technique would only add an additional pounds 300 to the cost of fertility treatment.
In Britain, the average live birth rate from fertile couples is 20 per cent per treatment cycle. For those over 40 years old this falls to less than 10 per cent per cycle.
The actress Patricia Hodge is one of a string of well-known women having children later in life. She gave birth to her first child at the age of 42. Three years later, another son was born. Jane Seymour gave birth to twins at 44 while Britt Ekland had her son at the age of 45.Reuse content