The timing of embryo transfer, which aligns with different stages of embryo development, is an important element of in vitro fertilisation (IVF). This article briefly describes the main phases of IVF treatment, embryo development and transfer policies, cumulative live birth rates, and the key findings of the authors’ research. In vitro fertilisation (IVF) is a well established treatment for infertility and has been responsible for the birth of more than 10 million children worldwide since 1978.1 An IVF cycle includes ovarian hyperstimulation with hormones, oocyte retrieval, and then fertilisation and embryo culture in the laboratory.23 In most laboratories worldwide, embryos are cultured in vitro for three to six days, and the embryos with the highest chance of resulting in a live birth are selected for intrauterine transfer. Surplus embryos are cryopreserved for future use if a live birth is unsuccessful after an initial transfer or more children are planned. IVF, with or without intracytoplasmic sperm injection (ICSI), involves the handling of sperm cells and oocytes (gametes) and embryos outside the human body. In IVF, thousands of sperm cells are used to inseminate oocytes in the …

中文翻译：

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体外受精过程中胚胎移植当天的重要性


胚胎移植的时机与胚胎发育的不同阶段相一致，是体外受精（IVF）的重要组成部分。本文简要介绍了体外受精治疗的主要阶段、胚胎发育和移植政策、累积活产率以及作者研究的主要发现。体外受精 (IVF) 是一种成熟的不孕不育治疗方法，自 1978 年以来，全世界已有超过 1000 万儿童出生。1 IVF 周期包括用激素过度刺激卵巢、取出卵母细胞，然后在实验室进行受精和胚胎培养。 .23 在世界各地的大多数实验室中，胚胎在体外培养三到六天，然后选择活产机会最高的胚胎进行宫内移植。如果初次移植后活产不成功或计划生育更多孩子，多余的胚胎将被冷冻保存以供将来使用。 IVF，无论有或没有胞浆内单精子注射 (ICSI)，都涉及在人体外处理精子细胞、卵母细胞（配子）和胚胎。在体外受精中，数千个精子细胞被用来使卵母细胞受精……