P-297 Comprehensive artificial intelligence-powered investigation of blastocyst expansion dynamics: associations with competence

Abstract Study question Are blastocyst expansion dynamics from time of starting blastulation (tSB) to biopsy (t-biopsy) indicative embryo competence? Summary answer Early across 5hours after tB, embryo-proper area (emb-A), zona-pellucida-area (zp-A), ZP-thickness (zp-T) at t-biopsy and their t-biopsy/tB ratios are associated with competence. What is known already Blastocyst the very first morphogenetic event common several species. Time-lapse-technology (TLT) implementation in IVF allowed deeper understanding process. Some studies leveraged TLT Artificial-Intelligence investigate timings for association Huang’s group, particular, designed a quantitative standard assay (qSEA) showing promising results. However, data about qSEA reproducibility missing. Here we comprehensively investigated processes between tSB through Artificial-Intelligence, adapted our setting that encompasses PGT-A without day3-hatching single-euploid-blastocyst-transfer. design, size, duration Retrospective study including 2184 blastocysts cultured EmbryoScope during 786 cycles conducted 2013-2020. Videos were analyzed an Artificial-Intelligence-powered tool (CHLOE™, Fairtility). The software automatically extracted hours-post-insemination measures as proportions video frames occupied by each feature under investigation (single pixel = 300µm; wells’ 90,000µm2) recorded every 30min tSB. These tested euploidy live-birth 548 euploid transfers via multivariate regressions. Participants/materials, setting, methods ICSI, trophectoderm on fully-expanded day3 zp drilling, qPCR/NGS assess full-chromosome non-mosaic aneuploidies performed. assessed tSB, tEB ( end video). At these following emb-A, zp-A, zp-T, inner-cell-mass (ICM-A), ICM-to-trophectoderm ratio. Also increase/decrease all assessed. Putative confounders (e.g., maternal age, quality) considered. Main results role chance Larger emb-A zp-A zp-T both euploidy. Similarly, t-biopsy/tEB highlighted larger among versus aneuploid blastocysts. All differences confirmed when adjusting morphological quality tB (p < 0.01). ratio (aneuploid:+68.8% euploid:+79.9%) showed more relevant than final per se (24082 ± 5763 25438 5969µm2). also significantly euploidy, even In this case, (8.1 3.2 7.1 2.7µm) stronger (-50% -55%). ICM-A no features LBs (N 233/548 transfers). outlined different early blastocysts, former expanding (larger areas thinner zp) sooner. became significant 2.5-3 hours, due rather constant rates groups, but faster euploid. same trend was reported resulting LB not. Limitations, reasons caution single-center study. Previous based 10 measurements hour instead 30min. To properly LB, required. outline predictive power, instead, prospective randomized design warranted. Wider implications findings dynamics, measured provide objective clinical strategy, user-friendly easily applicable, deserves further appraisal. Basic research mechanisms govern Trial registration number None