Factors that could influence pgt-a results: amh levels and their impact on embryo ploidy

Embryo chromosome abnormalities are the most common cause of pregnancy loss, occurring in up to 60% of miscarriages. Preimplantation genetic testing for aneuploidies (PGT-A) is employed to select euploid embryos for transfer. The association between advanced maternal age and an increased risk of chromosomal abnormalities in embryos is well known. Furthermore, other possible factors contributing to the incidence of aneuploidy in human embryos have been proposed. For instance, some authors have associated a reduced ovarian reserve and the number of oocytes retrieved with a higher aneuploidy rate. However, contradictory results have been reported and controversy remains. The objective of this study was to evaluate the influence of ovarian reserve, oocyte retrieval, MII oocytes, and fertilization rate on PGT-A results. This was a retrospective, single-center study conducted between 2016 and 2022 that included 2617 blastocysts from patients undergoing intracytoplasmic sperm injection (ICSI) and PGT-A at the blastocyst stage on days 5, 6 or 7. PGT-A was performed using Next Generation Sequencing (NGS) (Veriseq, Illumina). Embryos were classified according to the NGS results as euploid, aneuploid, or mosaic. The latter group was excluded from the analysis. Only autologous blastocysts were assessed. Blastocysts were first divided according to maternal age (≤37 or >37 years) and then according to their ploidy results in euploid or aneuploid. The following variables were assessed: anti-Müllerian hormone (AMH), follicle-stimulating hormone (FSH), luteinizing hormone (LH), estradiol (E2), antral follicular count (AFC), retrieved oocytes, MII oocytes, and fertilization rate. Patients with AMH values >4.7ng/ml were excluded. Differences between groups were compared using t-tests. A p-value <0.05 was considered statistically significant. Data analysis was performed using RStudio V1.3. The mean (±SD) maternal age was 33.6 (±3.0) and 40.6 (±1.9) in the groups of ≤37 and >37 years, with 770 and 1344 embryos in total, respectively. In the ≤37 group, PGT-A analysis resulted in 533 (69.2%) euploid and 237 (30.8%) aneuploid blastocysts; and in the >37 years group 472 (35.1%) were euploid and 872 (64.9%) aneuploid. As expected, statistical differences were observed in embryo ploidy in the ≤37 and >37 years groups (p<0.05). In the ≤37 years group, the only variable with a significant difference in ploidy rate was AMH. The mean AMH value was 2.4 ng/ml (±1.1) in euploid and 2.08 ng/ml (±1.09) in aneuploid blastocysts. No significant differences were found in the >37 years group for all the variables studied. Our results would indicate that among different variables that evaluate ovarian reserve, only AMH values could have an impact on ploidy in younger patients. Further studies with larger sample sizes are needed to unveil a significant impact on clinical outcomes.