随着体外受精-胚胎移植(IVF-ET)技术的不断进步,如卵巢刺激方案和胚胎培养技术的革新,已促使妊娠率大幅度提高,而伴随的多胎妊娠率也升高.多胎妊娠危及母婴的安全,有悖于优生原则.减少移植胚胎的数目,推行单胚胎移植是降低多胎出生最为有效的措施,但困扰胚胎学家的是如何选择最具有发育潜能的胚胎用于移植.目前,胚胎体外发育潜能的评估方法仍主要依据胚胎形态学的评分,其他选择方法,如对胚胎的蛋白组学和代谢组学等方法的研究还很难被广泛地应用,仍无法代替简便、快捷、又不失效率的形态学评估方法.受配子/胚胎自身因素以及体外操作、培养环境的影响,胚胎在体外发育过程中常伴随出现一些形态学上的异常现象,而这些形态学特征往往与其发育潜能相关,但形态学并不能完全准确地反应配子/胚胎的发育潜能,尤其是单一时间点的形态学评分,因此综合考虑配子至胚胎各个阶段的形态学评分将有助于选择较高发育潜能的胚胎用于移植.%Multiple birth is the biggest risk to the health and welfare of children born after IVF. Reduction the number of embryos transferred is effective strategy to reduce the incidence of multiple pregnancies after IVF. However, the main problem is how to select the best quality embryo for transfer. Currently, the morphological scoring continues to be the primary tool for embryo selection and transfer. Throughout pre-implantation development, embryos must undergo a series of critical events, I. E. , the fertilization process, the first mitotic divisions, the activation of the embryonic genome, and blastomere compaction and cavitation, ending with the formation of an expanded blastocyst. The embryo development is usually companied with one or more atypical morphology in vitro, such as fragmentation, uneven blastomeres, low or fast development rate, multi-nucleation of blastomere, vacuoles. Atypical development may indicate the low development potential of human embryo. Recently, a method of sequential morphological scoring for embryo selection has been recommended. Taking into account many morphological parameters of different stages of embryo will help us to select the embryos of higher developmental potential.
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