Genetic Infertility Testing

Both eggs and embryos can now be genetically screened for specific genetic abnormalities with advanced genetic techniques. The basic screening technique, which has been used with success for over 20 years, is called pre-implantation genetic diagnosis (PGD). Originally, PGD was developed as a detection method to determine genetic alterations in embryos of couples who were at risk of passing on an inherited disease to their children. These couples were usually fertile. They needed in vitro fertilisation (IVF) to provide embryos for analysis and a few of the embryos could then be “diagnosed” as not affected by a genetic alteration.

In recent times, PGD technology has been used for infertile couples during IVF treatment to improve the success rates for IVF. The IVF embryos are assessed to identify chromosomally normal embryos for the transfer process. There is mounting evidence that miscarriages and failed IVF implantations are mainly due to a chromosome imbalance within the embryo. This is why the PGD technique involving screening of the embryo or egg is perhaps especially worthwhile for those women with a miscarriage history, with failed IVF cycles, and in those women with an older maternal age (the risk of your baby having a chromosome abnormality increases as you age. For example, Downs syndrome is due to an extra copy of chromosome 21.) Any couple who have previously had a pregnancy that was diagnosed with a chromosome abnormality should consider undergoing PGD.

The latest PGD techniques for embryo screening use a method called array comparative genomic hybridisation (CGH). All of the chromosomes can be assessed with only low-risk embryos being selected for the embryo transfer.