P-261 Embryo compaction based on time-lapse imaging is a valuable parameter for selecting blastocysts with the highest developmental potency and associated with a ploidy state

Abstract Study question Does embryo compaction positively correlate with blastocyst development and further embryonic ploidy status? Summary answer Fully compacted embryos develop into good-quality blastocysts, have shorter developmental times, are related to status. What is known already To succeed in assisted reproduction technique (ART), it necessary select that the highest potential. So, numerous studies make an effort establish parameters for selecting embryos. A Time-lapse system (TLS) allows embryologists understand dynamic change through continuous monitoring. In development, undergo functional changes during compaction, which play a crucial role formation. It also genome activation can be seen compaction. Incomplete leads failure. Nevertheless, details about of human not been paid sufficient attention, so still rarely known. design, size, duration This was retrospective cohort study including couples underwent IVF cycle at CHA Fertility Center, Gangnam, between January 2019 October 2022. total 371 reached from 113 patients cultured TLS were analyzed. Among these, 94 blastocysts analyzed by preimplantation genetic testing aneuploidy (PGT-A). Statistical analysis performed prism9 using t-test chi-square test. P values <0.05 regarded as statistically significant. Participants/materials, setting, methods Embryos classified two categories pattern: fully (Group1, N = 194) partially (Group2, 177). Blastocyst quality determined morphology divided three groups (Good, Average, Poor). The time ranging morula annotated based on scope image. surface measured every hour starting formation (tB) ellipse tool Embryo Viewer software. Main results chance Good average significantly higher Group 1 than 2 (21.6% vs. 3.4%, p < 0.01; 47.9% 26.6%, 0.01, respectively). contrast, poor-quality lower (30.4% 70.1%, 0.01). beginning completion times those 2(78.6h 82.4, 87.0h 92.2h, 100.2h 103.7, Also, there significant difference longitudinal area 3, 6, 12h tB groups. Consequently, expansion rate faster (653.6 μm2/hour 499.2μm2/hour, 0.05). According result PGT-A, had euploid rates compared (47.2% 36.2%, 0.001; 52.8% 63.8%, 0.001, However, PGT-A group, no groups, regardless or partial Meanwhile, euploidy (747.8 564.3 μm2/hour, Limitations, reasons caution main limitation single-center approach. Therefore future prospective research needed verify extend our findings. Another one, reason we selected biopsy. Wider implications findings Using TLS, observed dynamics detail. We found positive relationship its association ploidy. assessment parameter predicting competent should given priority when blastocysts. Trial registration number Not applicable