Abstract:

BACKGROUND: Some reports have showed that the discarded embryos can be used to establish the human embryonic stem cell lines, after freezing and thawing, the transplantation of embryos that hysteretic in morphological development still has medical value.
OBJECTIVE: To study the potential of discarded embryos cultured into blastocyst in vitro.
METHODS: Totally 404 discarded embryos were collected from the patients treated with in vitro fertilization and embryo transfer (IVF_ET) or intracytoplasmic sperm injection (ICSI), and then preformed with blastocyst sequential training.
RESULTS AND CONCLUSION: ①The 404 discarded embryos formed 65 blastocyst, the total blastocyst formation rate was 16.1%. ②There was no relation between the blastocyst formation and the patient's etiology, age, fertilization methods (P > 0.05). ③The blastocyst in embryos derived from the ≥ 3 pronuclear (PN) embryos (6-8) cell group had the highest formation rate    (P < 0.05). The number of blastomeres increased with the number of cells and the blastocyst rate was also increased, but, when the cell number was more than 8, the blastocyst rates was dropped, and similar to < 3 cell group. ④The Ⅰ and Ⅱ embryos with the a high blastocyst formation rate that was higher than Ⅲ and Ⅳ embryos (P < 0.05). ⑤The clinical pregnancy rate of the patients with blastocyst formation was higher than those without blastocyst formation (P < 0.05). The blastocyst formation has no relation with the etiology of patients, age and fertilization methods. The good quality embryos and (6-8) cell embryos has the highest blastocyst formation rate, and the blastocysts formation value of the pronuclear embryos should be caused for concern. The recycle of the discarded embryos can predict clinical outcomes and provide favorable land resources for human embryonic stem cells.