PGS: a four-letter word?

Preimplantation genetic screening (PGS) involves the identification of chromosome abnormalities in IVF embryos (rather than targeting diagnosis to a specified gene). Chiefly employed for couples with advanced maternal age, recurrent miscarriage or recurrent IVF failure, it aims to improve IVF success, and reduce miscarriage and affected live birth rates. The process involves the sampling of cells by embryo biopsy, cytogenetic diagnosis, then selective transfer of an apparently chromosomally normal embryo in the hope of establishing a pregnancy. Although PGS is the most common variant of PGD (preimplantation genetic diagnosis), accounting for 80% of cases it has, from the outset, been one of the most controversial areas of reproductive medicine. The subject of intense debate, it attracts opinions ranging from recommendations that it should be applied in all IVF cases, through to the suggestion it should be discontinued completely. What do you think? Should it continue or not?