Tesarik J, Greco E
Laboratoire d'Eylau, 55 Rue Saint-Didier, 75116 Paris, France.
Hum Reprod. 1999 May;14(5):1318-23. doi: 10.1093/humrep/14.5.1318.
This retrospective study was undertaken to determine whether further developmental progression of two-pronucleated (2PN) zygotes can be predicted by a single, non-invasive examination of pronuclei, with the use of criteria based on the number and distribution of nucleolar precursor bodies in each pronucleus. The normal range of pronuclear variability was defined by analysis of zygotes giving rise to embryos transferred in 100%-implantation cycles (pattern 0). Morphological patterns differing from pattern 0 were classified as patterns 1-5. The frequency of developmental arrest of pattern 0 zygotes was only 8.5% as compared with 31.6, 21.9, 30.0, 20.5 and 24. 1% for patterns 1-5 respectively. Relationships of pronuclear patterns with blastomere multinucleation and cleaving embryo morphology were also noted. Clinical pregnancy was achieved in 22 of 44 (50%) treatment cycles in which at least one pattern 0 embryo was transferred, but only in two of 23 (9%) cycles in which only pattern 1-5 embryos were transferred. These data present new evaluation criteria which can be used to predict the developmental fate of human embryos as early as the pronuclear stage, without requiring repeated observations or an exact timing of pronuclear zygote inspection. Further prospective study is needed for clinical validation of these criteria.
本回顾性研究旨在确定通过对原核进行单次非侵入性检查，利用基于每个原核中核仁前体的数量和分布的标准，是否能够预测双原核（2PN）受精卵的进一步发育进程。通过分析在100%着床周期中移植胚胎的受精卵来定义原核变异的正常范围（模式0）。与模式0不同的形态学模式被分类为模式1 - 5。模式0受精卵的发育停滞频率仅为8.5%，而模式1 - 5的分别为31.6%、21.9%、30.0%、20.5%和24.1%。还注意到原核模式与卵裂球多核化和分裂胚胎形态的关系。在44个治疗周期中的22个（50%）中实现了临床妊娠，这些周期中至少移植了一个模式0胚胎，但在仅移植模式1 - 5胚胎的23个周期中只有2个（9%）实现了临床妊娠。这些数据提出了新的评估标准，可用于早在原核阶段预测人类胚胎的发育命运，而无需重复观察或精确确定原核受精卵检查的时间。这些标准的临床验证还需要进一步的前瞻性研究。
