Embryonic Cell-free DNA in Spent Culture Medium: A Non-invasive Tool for Aneuploidy Screening of the Corresponding Embryos.

Background/aim Preimplantation genetic testing (PGT) for chromosomal screening, based on embryo biopsy, has significant limitations. Cell-free DNA (cf-DNA) has been detected in spent culture medium (SCM), opening new horizons for the development of non-invasive PGT (ni-PGT). In this study, we evaluated the diagnostic performance of ni-PGT for aneuploidy (niPGT-A), comparing the results of trophectoderm biopsies (TE) and respective SCM from individually cultured embryos via Next Generation Sequencing (NGS). Materials and methods Forty fresh embryos were analyzed. TE and SCM from blastocysts were collected and analyzed. Results We detected cfDNA in 100% of samples tested. The overall concordance rate between the ni-PGT-A and PGT-A was 27/33 (81.8%). The full concordance rate was 21/33 (63.6%). The aneuploidy agreement was 91.66%, and the euploidy agreement was 76.19%. Conclusion We found a good accordance between TE and SCM analysis, suggesting that niPGT-A could be a reliable alternative for chromosomal abnormalities assessment of in vitro cultured embryos.