Preimplantation genetic screening

Abstract

Chromosome aneuploidy is naturally occurring, typically sporadic and generally leads to non-viable offspring. The use of PGS has the potential to select the best embryos for transfer and reduce the risk of losing a much wanted pregnancy. However there is no high-level clinical evidence from randomized control trials to demonstrate a beneficial effect of PGS on the live birth rate after IVF, and for women of advanced age, PGS using cleavage stage biopsy and FISH may lead to a significant decrease in live birth rates. Technical limitations and chromosomal mosaicism confound the effectiveness of PGS, but a test that could identify aneuploidy with 100 % accuracy would be a significant advance; no such test has yet been developed. New approaches in the application of PGS should be evaluated carefully before their introduction into clinical practice.