MITOCHONDRIAL CONTENT IN EUPLOID BLASTOCYST IS ASSOCIATED WITH BLASTOCYST´S DAY OF DEVELOPMENT

Recently, the mitochondrial DNA content (mtDNA) has been proposed as a new parameter with high predictive value for embryo viability. The aim of this retrospective study was to evaluate relationship between mtDNA and blastocyst´s day development biopsy day. Embryos resulting from patients, who started fresh intracytoplasmic sperm injection (ICSI) cycles were incubated in K-System® G-18 or ThermoFisher Scientic® Heracell 150i incubators Sage® Medium Global Total® Medium. Laser-assisted (Lykos, Hamilton Thorne®) performed on 5/6/7 blastocyst embryos vitrified soon after according validated protocol (Kitazato®). Chromosome testing conducted by Next-Generation Sequencing (NSG) at Igenomix® molecular biology laboratory surplus amplified euploid used obtain values, “MitoScore” (Ms). That included result reports. We total 69 patients 23 49 years old undergoing pre-implantation genetic aneuploidy (PGT-A) period 2019-2021. copy number blastocysts examined 144 trophectoderm biopsies. Blastocysts divided into 3 groups, their day: G1) 5 blastocysts; G2) 6 G3) 7 blastocysts. Kruskall-Wallis test analyze difference among groups. Statistical represented p<0.05. When examining values studied we obtained following results: median (G1) 22,71 (n=94); (G2) 29,28 (n=43) and, finally, (G3) 30,25 (n=7). showed that there is evidence consider Ms associated (p< 0,0001). Determinants such age, morphology infertility diagnosis homogeneously distributed Our findings suggest MitoScore significantly different depending