BLASTOCYST MORPHOLOGY AS A PREDICTOR OF EUPLOIDY: A RETROSPECTIVE ANALYSIS OF PGT-A CYCLES
DOI:
https://doi.org/10.32782/1998-6475.2025.59.24Keywords:
blastocyst, embryo morphology, euploidy, preimplantation genetic testing for aneuploidy (PGT-A), assisted reproductive technologies (ART), embryonic anatomy, developmental physiologyAbstract
The aim of this study was to evaluate the association between blastocyst morphology and chromosomal status in Assisted Reproductive Technology (ART) programs, given that a significant portion of morphologically highquality embryos can be aneuploid and that existing literature presents contradictory findings on this correlation. A retrospective cohort study was conducted at «Plusmed» Medical Center (Uzhhorod, Ukraine) from January 2023 to March 2025. The results of 43 PGT-A cycles were analyzed, during which 164 blastocysts were biopsied. Embryos were classified into three quality groups (good, fair, and poor) based on Inner Cell Mass (ICM) and Trophectoderm (TE) grades. Euploidy rates were compared across quality groups and stratified by two female age groups (≤35 and >35 years). Multivariate logistic regression was used to assess the association and adjust for potential confounders (maternal age, BMI, duration of infertility, etc.). The overall euploidy rate among 160 analyzed blastocysts was 41.25%, with an aneuploidy rate of 46.88%. A clear positive correlation was established between morphological quality and the probability of euploidy (p < 0.001). Blastocysts of good (65.22%) and fair (55.32%) morphology showed significantly higher euploidy rates compared to those of poor morphology (27.78%). The odds of being euploid were 2.9 times higher for good-quality (OR=2.900) and 1.8 times higher for fair-quality (OR=1.828) embryos compared to poor-quality embryos. This trend persisted in both age groups: in women ≤35 years (Good 71.43%, Fair 56.67%, Poor 28.81%) and in women >35 years (Good 55.56%, Fair 52.94%, Poor 25.81%). A significant nonlinear correlation (R²=0.9342) was also observed between increasing female age and the decreasing likelihood of obtaining euploid embryos. Blastocyst morphology may serve as an important, independent predictor of chromosomal status. Embryos with low morphological scores are characterized by a significantly reduced euploidy rate. However, as a notable portion of aneuploid embryos can still exhibit «good» morphology, morphological assessment is not an absolute criterion and should not be the sole selection criterion for embryo transfer.
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