JBRA Assisted Reproduction 2025;29(Suppl.2 SBRA 2025):91
Poster Presentation
29^th Annual Congress of the SBRA. São Paulo/SP - Brazil, 2025
doi: 10.5935/1518-0557.20263671

P-79. Elevated mitochondrial DNA is associated with inferior morphology in euploid embryos subjected to embryo biopsy

Vanesa Cristina Freitas Moreno¹, Sarah Junkes¹, Grazielle Alves Bento¹, Luciano Brandão Proença Bettega¹, Renato Pegorim Filho

¹ Fertvita Medicina Reprodutiva - Balneário Camboriú - SC - Brasil

Objective: To investigate the association between mitochondrial DNA (mtDNA) quantity and embryonic morphology in euploid blastocysts undergoing embryo biopsy.
Methods: An ongoing prospective study including 30 single euploid blastocyst transfers with a mean maternal age of 37 years. mtDNA was quantified by next-generation sequencing (NGS) and expressed as the ratio of mitochondrial DNA to nuclear DNA. Embryos were classified into three groups: *Low mtDNA (<18.19): high implantation potential * Medium mtDNA (18.19–24.15): medium implantation potential *High mtDNA (>24.15): low implantation potential Inner cell mass (ICM) and trophectoderm (TE) morphology were evaluated using Gardner's scale (A, B, C). The primary clinical outcome was implantation rate (positive beta-hCG). Statistical analyses included ANOVA with Bonferroni post-test and Fisher's exact test for implantation rates.
Results: Thirty embryos were evaluated: *Low mtDNA (n=14): 64.3% implantation (9/14) *Medium mtDNA (n=15): 53.3% implantation (8/15) *High mtDNA (n=1): 0% implantation (0/1). No statistically significant difference in implantation rates was observed between mtDNA groups (Fisher's exact test: p=0.71 for low vs medium; p=0.40 for low vs high). Mean mtDNA values according to ICM classification were: *ICM A: 17.54 *ICM B: 17.69 ICM C: 30.05 (p=0.0041; ANOVA). A significant association was found between elevated mtDNA levels and embryos with ICM type C. No statistical correlation was found between mtDNA levels and TE classification.
Conclusion: Although mtDNA alone did not correlate with implantation rates, combined analysis with ICM morphology revealed that embryos with ICM type C had significantly higher mitochondrial loads. mtDNA assessment may thus serve as a complementary tool to morphology in selecting euploid embryos. The study is ongoing with sample size expansion for validation.