Institute of Sciences in Human Reproduction "Vida", Guanajuato, Mexico.
JBRA Assist Reprod. 2023 Sep 12;27(3):453-462. doi: 10.5935/1518-0557.20230011.
To compare the preimplantation genetic testing for aneuploidy (PGT-A) results using the three most frequent criteria employed by preimplantation genetic laboratories and evaluate its impact on the number of euploid embryos available for transfer.
Retrospective and descriptive study including patients who underwent PGT-A between January 2018 and December 2020. Five hundred and nine PGT-A cycles and 2,079 blastocysts were analyzed by next-generation sequencing (NGS). We re-assigned the diagnosis of all blastocysts using three different criteria: strict (mosaicism thresholds from 20% to 80%), standard (from 30% to 70%) and excluding (mosaicism is not reported). We compared the euploid, aneuploid and mosaic embryos obtained in each criteria used.
We observed PGT-A results discrepancies in 32.5% (165/509) of the cycles when the three different criteria were applied. The standard and excluding criteria showed 92 more euploid embryos (875/2,079) compared to the strict criteria (783/2,079). Evaluating the PGT-A results per cycle with the strict, standard and excluding criteria, the euploidy rates were 34.0%, 38.4% and 38.4% (p<0.001); aneuploidy rates were 59.0%, 55.8% and 61.6% (p<0.001) and mosaic rates were 7.0% and 5.8% (p<0.047), respectively. The mean number of euploid blastocysts available for transfer was 1.54±1.67 with the strict criteria, while the possibility to obtain an euploid embryo was higher if the standard or the excluding criteria were used 1.72±1.78 (p<0.001).
This study highlights the importance of standardizing the criteria used for the interpretation of PGT-A blastocysts. We observed significant differences on PGT-A results associated solely to the criteria used.
比较胚胎植入前遗传学检测（PGT-A）中使用的三种最常见的标准，评估其对可用于移植的整倍体胚胎数量的影响。
这是一项回顾性描述性研究，纳入了 2018 年 1 月至 2020 年 12 月期间接受 PGT-A 的患者。通过下一代测序（NGS）对 509 个 PGT-A 周期和 2079 个囊胚进行分析。我们使用三种不同的标准重新分配所有囊胚的诊断：严格标准（嵌合体阈值为 20%-80%）、标准标准（嵌合体阈值为 30%-70%）和排除标准（不报告嵌合体）。我们比较了在每个标准中获得的整倍体、非整倍体和嵌合体胚胎。
当应用三种不同的标准时，我们观察到 32.5%（165/509）的周期存在 PGT-A 结果不一致。与严格标准（783/2079）相比，标准标准和排除标准显示有 92 个额外的整倍体胚胎（875/2079）。按严格、标准和排除标准对每个周期的 PGT-A 结果进行评估，整倍体率分别为 34.0%、38.4%和 38.4%（p<0.001）；非整倍体率分别为 59.0%、55.8%和 61.6%（p<0.001），嵌合体率分别为 7.0%和 5.8%（p<0.047）。严格标准下可用于移植的整倍体囊胚的平均数量为 1.54±1.67，而使用标准或排除标准获得整倍体胚胎的可能性更高，分别为 1.72±1.78（p<0.001）。
这项研究强调了标准化胚胎植入前遗传学检测囊胚解读标准的重要性。我们观察到仅与使用的标准相关的 PGT-A 结果存在显著差异。
