The evolution of preimplantation genetic testing: where is the limit?

Abstract

Preimplantation genetic testing (PGT) has revolutionized reproductive medicine over the past 30 years, providing a reliable method for reducing the risk of transmitting severe inherited conditions and offering the possibility of improved IVF outcomes. Today, PGT is widely accepted and integrated into fertility care in many countries around the world. Its history, however, has not been without controversy, with debate around its application to the diagnosis of late-onset disorders, conditions with incomplete penetrance and its use for embryo selection based upon human leukocyte antigen status. Nonetheless, PGT has progressively broadened its scope, and the number of embryos undergoing genetic testing continues to grow each year. Preimplantation genetic testing is most often used for the detection of chromosomal abnormalities, assisting in the identification of embryos affected by lethal aneuploidy. This application has generated the greatest debate of all, owing, in part, to difficulties delivering effective embryo testing using earlier methods. In recent years, advances in technology and rigorous validation studies have helped to improve accuracy, although variability among methods underscores the need for greater standardization and transparency. Emerging technologies, such as whole genome sequencing (WGS) and genome editing, hold promise for further advancements but introduce complex ethical, privacy and consent challenges that demand careful consideration, public engagement and thorough clinical research before implementation. Given its current trajectory, it seems likely that the use of PGT will continue to grow, offering reduced reproductive risks and the possibility of enhanced fertility treatment outcomes for ever greater numbers of patients, ultimately becoming an accepted cornerstone of reproductive care.