A prospective, blinded, non-selection study to determine the predictive value of ploidy results using a novel method of targeted amplification based Next generation sequencing (NGS) for comprehensive chromosome screening (CCS)

Abstract

NGS technologies are now being utilized for CCS with promises to increase throughput and decrease costs. Unfortunately, these technologies have not been validated clinically. Most concerning is the lack of data documenting the false abnormal rate, defined as the proportion of embryos labeled as aneuploid through NGS but which would have delivered a healthy infant had they not been discarded. This study utilizes a non-selection design where embryos are transferred without knowledge of the NGS CCS result to determine the predictive value of both aneuploid and euploid results. Prospective, blinded, non-selection study. Patients with normal ovarian reserve ≤ 42 years of age were recruited. Following routine IVF care, trophectoderm biopsy was performed. Embryos were subsequently selected for transfer per routine. No NGS CCS analysis was done prior to transfer. A novel targeted amplification method of NGS based CCS which does not require whole genome amplification was then performed. The outcome for each transferred embryo was compared to the NGS screening result to determine the predictive value of that result. In the case of a two embryo transfer, DNA fingerprinting was utilized to ensure that the embryo responsible for the pregnancy was identified correctly. Implantation rates were compared between embryos designated euploid, aneuploid, and for the population as a whole. 117 patients had 187 blastocysts transferred. Of the 41 embryos assigned an aneuploid karyotype, none sustained implantation yielding a predictive value of an aneuploid result of 100%. 97 of 146 embryos designated as euploid implanted and progressed to delivery yielding a predictive value for a euploid result of 66.0%. No embryo designated as euploid subsequently developed into an aneuploid gestation. Euploid embryos had a higher sustained implantation rate than the population as a whole (50.8%, p<0.0001) and those designated aneuploid (0%, p<0.0001). This study represents the first prospective clinical evaluation of the predictive values of both a euploid and an aneuploid result when using NGS based CCS. This targeted amplification NGS CCS paradigm has a high degree of precision and provides excellent predictive values for actual clinical outcomes.