A fertility clinic in Nottingham announced the world's first pregnancy using a new genetic screening technique aimed at reducing the high failure rate of in vitro fertilization.

The woman in question is a 41 year old who is scheduled to give birth in Nottingham sometime in late spring. Wishing to remain anonymous the woman who is six months pregnant had previously undergone 13 unsuccessful IVF cycles and three miscarriages.

The team at CARE Fertility clinic said they have found a way of extracting a "spare" set of chromosomes inside the egg and rapidly analyzing them. Chromosomal abnormalities in the eggs are one of the reasons that IVF fails and scientists under the new technique claim to be able to detect irregularities without having to freeze embryos. This they believe has the potential to significantly improve a couples success chances.

An egg should have just 23 chromosomes which contain the woman's share of the genetic code with the other half coming from the sperm after fertilization. The spare chromosomes in the egg are found near its edge in what is known as the polar body.

Under the new technique called array CGH (Comparative Genomic Hybridization), a laser is used to cut a hole in the edge of the egg and with the help of a pipette, the polar body is removed. The scientists then analyze the chromosomes inside the polar body which should be a mirror image of those left in the egg and can be easily examined without disturbing the egg.

If the scientists find that there is a chromosome missing from the egg, then they would know that any subsequent embryo will fail despite it having a healthy appearance when viewed through a microscope. The presence of an extra chromosome could indicate a miscarriage or a pregnancy with an inherited genetic disorder.

Dr Simon Fishel, director of the CARE fertility group said, "We know that at least half the eggs and embryos produced are wasted due to chromosomal abnormalities.

"If we could choose those with normal chromosomes logic tells us we double the chances of pregnancy and that's what we hope." This technique he said would also reduce the chances of twins and triplets which are the signature of fertility treatments. "In this country we have to reduce the incidence of multiple pregnancy and there's a big drive to put a single embryo back. "

That could reduce all women's chances of pregnancy but not if we choose the embryo that is most viable and has normal chromosomes.

"Ultimately we could reach the holy grail of one cycle of IVF, one egg, one embryo and one baby."