Non-invasive chromosome testing (NUCT) improved in vitro fertilization (IVF) outcomes compared to morphological assessment in single blastocyst transfer (SBT)

Abstract

Introduction Pre-implantation screening (PGS) has been widely used in assisted reproductive technology (ART) and helped improve in vitro fertilization (IVF) clinical outcomes. However, the invasive blastomere or trophectoderm biopsy process involved in PGS not only could generate potential effects on embryo development but requires skills and experience. Non-invasive chromosome screening (NICS) method, which using MALBAC technique to amplify the genomic DNA secreted into the culture medium and following next generation sequencing (NGS) to analysis ploidy condition of the embryos, had been validated through in vitro study(J. Xu et al. 2016 ). Here we further investigate NICS potentials on IVF. Material & Methods A retrospective observational study from September 2015 to September 2016. A total of 353 frozen-thawed single blastocyst transfer (SBT) cycles were divided into three groups with different blastocyst selection criteria: the first was the No-choice group which had only one blastocyst for transfer for each patient (n=285). The second was the Morphology group. The patients of this group had at least two blastocysts available and blastocysts were selected for single blastocyst transfer on the basis of traditional morphological assessments (n=41); the third was the NICS group that had at least two blastocysts for each patient and the euploid blastocysts were selected using NICS for single blastocyst transfer (n=27). Results The biochemical pregnancy rate in the No-choice group, the Morphology group and the NICS group was 65.3%, 65.9% and 85.2%, respectively (P=0.232). Among three groups, the NICS group had the highest implantation rate (63.0%) (P=0.193), compared with 56.1% and 45.3% in the Morphology group and the No-choice group, respectively. There was no incidence of early miscarriage in the NICS group, while the early miscarriage rate in the No-choice group and the Morphology group was 21.1% and 13.0%, respectively (P=0.094). A significant difference was found in the ongoing pregnancy rate among the three groups, which was highest in the NICS group (63.0%) and lowest in the No-choice group (37.9%) (P=0.016). Conclusions NICS is a novel genetic testing that allows an accurate selection of blastocysts with better developmental potential for transfer and might improve the clinical outcomes.