Purpose

Before blastocyst development, embryos undergo morphological and metabolic changes crucial for their subsequent growth. This study aimed to investigate the relationship between morula compaction and blastocyst formation and the subsequent chromosomal status of the embryos.

Methods

This retrospective cohort study evaluated embryo development (n = 371) using time-lapse imaging; 94 blastocysts underwent preimplantation genetic testing for aneuploidy (PGT-A).

Results

The embryos were classified as fully (Group 1, n = 194) or partially (Group 2, n = 177) compacted. Group 1 had significantly higher proportions of good- and average-quality blastocysts than Group 2 (21.6% vs. 3.4%, p = 0.001; 47.9% vs. 26.6%, p = 0.001, respectively). The time from the morula stage to the beginning and completion of compaction and blastocyst formation was significantly shorter in Group 1 than in Group 2 (78.6 vs. 82.4 h, p = 0.001; 87.0 vs. 92.2 h, p = 0.001; 100.2 vs. 103.7 h, p = 0.017, respectively). Group 1 embryos had larger surface areas than Group 2 embryos at various time points following blastocyst formation. Group 1 blastocysts had significantly higher average expansion rates than Group 2 blastocysts (653.6 vs. 499.2 μm²/h, p = 0.001). PGT-A revealed a higher proportion of euploid embryos in Group 1 than in Group 2 (47.2% vs. 36.6%, p = 0.303).

Conclusion

Time-lapse microscopy uncovered a positive relationship between compaction and blastocyst quality and its association with embryo ploidy. Hence, compaction evaluation should be prioritized before blastocyst selection for transfer or cryopreservation.

中文翻译：

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用于选择高质量囊胚的桑葚胚压缩延时成像：一项回顾性队列研究

目的

在囊胚发育之前，胚胎会经历对其后续生长至关重要的形态和代谢变化。本研究旨在探讨桑葚胚压缩与囊胚形成以及随后胚胎染色体状态之间的关系。

方法

 这项回顾性队列研究使用延时成像评估了胚胎发育（n = 371）； 94 个囊胚接受了植入前非整倍体基因检测 (PGT-A)。

结果

胚胎被分类为完全压缩（第 1 组，n  = 194）或部分压缩（第 2 组，n  = 177）。第 1 组的优质囊胚和平均质量囊胚的比例显着高于第 2 组（分别为 21.6% 与 3.4%，p  = 0.001；47.9% 与 26.6%，p  = 0.001）。第 1 组从桑葚胚阶段到压实和囊胚形成开始和完成的时间明显短于第 2 组（78.6 小时 vs. 82.4 小时，p  = 0.001；87.0 小时 vs. 92.2 小时，p  = 0.001；100.2 小时 vs. 100.2 小时）。 103.7 小时，p  = 0.017，分别）。在囊胚形成后的不同时间点，第 1 组胚胎的表面积大于第 2 组胚胎。第 1 组囊胚的平均扩张率显着高于第 2 组囊胚（653.6 vs. 499.2 μm ² /h，p  = 0.001）。 PGT-A 显示第 1 组中的整倍体胚胎比例高于第 2 组（47.2% vs. 36.6%，p  = 0.303）。

结论

延时显微镜揭示了压实度和囊胚质量之间的正相关关系及其与胚胎倍性的关系。因此，在选择囊胚进行移植或冷冻保存之前，应优先考虑压实评估。