Applications

It is believed that about 70% of embryos resulting from IVF do not result in a birth. Aneuploidy is thought by many scientists to be a major cause of this embryo loss as, with the exception of a small number of chromosomes (for example chromosome 21, Downs Syndrome), aneuploid embryos are not viable.

It is known that miscarriage rates and incidence of Downs Syndrome increase significantly with maternal age, just as fertility declines. This together with recent research using advanced cytogenetic and molecular techniques supports the hypothesis that aneuploidy might also be considered when existing morphological and scorecard techniques are used for embryo selection.

The hope is that aneuploidy screening may improve outcomes, reduce miscarriage and reduce the incidence of multiple embryo transfer and associated multiple births. This potential lead the PGS Task Force of the European Society of Human Reproduction and Embryology to launch a two centre clinical study using 24sure in June 2009, the results of the study were announced in June 2010 and are discussed here. It is anticipated that the groups most likely to benefit from 24sure are:

Persistent IVF failure. Where three or more previous IVF cycles have failed without an obvious explanation.

Recurrent miscarriage. Where investigations have highlighted parental translocations as a possible cause of recurrent miscarriage.

PGD. Where PGD (preimplantation genetic diagnosis) has been used to identify embryos that are free from a pathogenic gene and the centre then wishes to select the embryo with the best chance of coming to term.