Preimplantation Genetic Screening: What 25 Years Has Taught Us

Abstract

The use of preimplantation genetic diagnosis (PGD) has expanded from being a method to prevent the transmission of know genetic defects, to becoming a screening tool, preimplantation genetic screening (PGS) to evaluate embryos for aneuploidy in the absence of a known genetic defect. The goal of PGS is to improve pregnancy rates by assessing the aneuploidy status of all embryos and transferring only those found to be euploid. Because this technology is progressing so quickly, there is a gap between typical practice and what may be possible through these new techniques. This article traces the 25-year history of PGD and PGS. It reviews the initial challenges, provides a summary of the advances in the technology, and describes how PGS and PGD can both increase pregnancy rates and decrease genetic conditions. After reading this article, the obstetrician/gynecologist should be better able to understand which patients would benefit from this technology, and appropriately refer patients for these techniques. Origins of PGD