Preimplantation Genetic Testing for Aneuploidy: A Review

Importance: Preimplantation genetic testing for aneuploidy (PGT-A) has undergone many technical developments over recent years, including changes in biopsy timings, methodology, and genetic analysis techniques. The evidence surrounding the efficaciousness of PGT-A is sporadic and inconsistent; as such, significant doubt and concern remain regarding its widespread implementation. Objective: This review seeks to describe the historical development of PGT-A and to analyze and summarize the current published literature. Conclusions: At times during its infancy, PGT-A failed to display conclusive improvements in results; with newer technologies, PGT-A appears to yield superior outcomes, including reductions in miscarriages and multiple gestations. Clinicians and patients should assess the use of PGT-A on a case-by-case basis, with laboratories encouraged to utilize blastocyst biopsy and next-generation sequencing when conducting PGT-A. Further studies providing cumulative live birth rates and time to live birth are required if PGT-A is to be proven as producing superior outcomes. Relevance: PGT-A has the potential ability to impact in vitro fertilization success rates, and as it is increasingly adopted worldwide, it is crucial that clinicians are aware of the evidence for its continued use. Target Audience: Obstetricians and gynecologists, family physicians. Learning Objectives: After reading this review, physicians should be better able to summarize the history of PGT-A, including the development over time of biopsy and analytical techniques; explain the continued uncertainty regarding the efficacy of PGT-A and the associated safety concerns; and assess the impact mosaicism may have on the interpretation of PGT-A results and subsequent treatment recommendations.