First aneuploidy screening success

An embryo screening technique that was licensed by the UK's Human Fertilisation and Embryology Authority (HFEA) last September has resulted in its first pregnancy in the UK. Two UK clinics were initially given licences to perform aneuploidy screening: CARE in the Park, Nottingham and the Assisted Reproduction and Gynaecology Centre in London. Another two clinics have been given a licence since then.

The procedure is only licensed for use in women over the age of 35 or for those who have a history of miscarriage or failed IVF treatment. The pregnant woman, who is 42 years old and now eight weeks pregnant, received treatment at CARE. Aneuploidy screening enables embryos to be tested for a range of chromosomal abnormalities and helps fertility doctors decide which embryos are best to implant.

The aneuploidy screening technique allows the chromosomes of an embryo - rather than its particular genes - to be studied in order to establish whether they contain any abnormalities. Aneuploidy is a condition in which an embryo contains the wrong number of chromosomes in each cell - this would normally prevent most embryos developing. It can also cause miscarriage or chromosomal conditions such as Down syndrome and is likely to be the cause of much 'unexplained infertility'. Aneuploidy is thought to affect 40 to 70 per cent of IVF embryos. After screening, embryos found to have the wrong number of chromosomes would not be used in treatment.

Dr Simon Fishel, director of CARE, said that two out of six embryos produced by the woman did not have genetic abnormalities and these were transferred to the woman. He commented that 'Nature produces a high percentage of abnormal embryos and simply looking down a microscope cannot detect these'. 'Using this technology we were able to select the only two chromosomally normal embryos for transfer to the womb', he added.