EC Gynaecology

The clinical value of PGT-A remains an area of debate. Most data produced so far demonstrate that the intervention of PGT-A is safe since they neither support nor refutes its efficacy. The clinical value of a test rests in its validity. A fair assessment and interpretation of results based on the original experimental design are key determinants of the accuracy of the reported outcomes. A significant issue concerning non-inferiority trials on PGT-A are flawed experimental set ups which invalidate many of the conclusions. We highlight and challenge some of these reports herein. Moreover, other relevant aspects related to the PGT-A reports concerns the discernment between technical and true biological mosaicism. This critical distinction is essential since reporting mosaicism may primarily come at the expense of euploid diagnoses. Other significant aspects impacting PGT-A outcomes are specifically related to the embryology laboratory. Technical manipulations for PGT-A need validation as well proved standardized results in order to substantiate clinical performances. These factors range from type of blastocysts biopsied, choice of biopsy procedure and individual performance. Overall, the controversies on the efficacy of PGT-A are, in part, due to the methodological limitations of studies which fail to consider the influence of the technical aspects on the outcomes.

Keywords: Preimplantation Genetics Testing for Aneuploidy (PGT-A); Trophectoderm Biopsy; Blastocyst; NGS; RCT

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