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Background: Aneuploidy is a leading cause of repeat implantation failure and recurrent miscarriages.Preimplantation genetic screening (PGS) enables the assessment of the numeric chromosomal constitution of embryos before transfer in patients undergoing in vitro fertilization (IVF).Array comparative genomic hybridization (array-CGH) has been demonstrated to be the gold standard PGS method in present, but new techniques, such as next-generation sequencing (NGS), continue to emerge.Validation of the new comprehensive technologies is still needed to determine the preclinical accuracy before they might be considered within the standard of care in reproductive medicine.Methods: 43 human embryo TE biopsy samples with known karyotype (41 abnormal and 2 normal) and 5 cytogenetically characterized cell lines (Coriell Cell Repositories) were tested.After whole genome amplification (WGA), all samples were processed with both NGS protocol and array-CGH protocol for aneuploidy status.Results: The same whole genome amplified product of each sample was blindly assessed with NGS and array-CGH to identify the aneuploidy status.The result shows that the NGS method identifies all abnormalities identified in array CGH.In total 1928 chromosomes were assessed, 53 resulted with a copy number imbalance, including 27 (50.9%) trisomies and 26 (49.1%) monosomies.The NGS method also identifies the same microdeletions and amplifications of Coriell cell lines as array CGH method,including regions of segmental imbalances, which were reliably identified with a segmental imbalance as small as 1.8 Mb in size.The sensitivity and specificity of NGS based PGS is 100%.Among the 41 TE cell samples with abnormal karyotype in this study, eight (19.5%) samples presented as multiple chromosome abnormalities.The abnormalities occurred to almost all the autosomes and sex chromosomes, except chromosome 6, 7, 17 and Y.Conclusions: Given its reliability and high level of consistency with an established methodology, such as array-CGH, NGS has demonstrated a robust high-throughput methodology ready for extensive clinical application in reproductive medicine, with potential advantages of reduced cost and enhanced precision.Then, a randomized controlled clinical trial confirming its clinical effectiveness is advisable to obtain a larger sequencing dataset and more evidence for the extensive use of NGS-based PGS.