Abstract: The incomplete oocyte activation is one of the main causes of fertilization failure or low fertilization after intracytoplasmic sperm injection （ICSI）. Fertilization rate and embryo developmental potential of haploid round/elong spermatid （RS/ES） were lower than those of mature spermatozoa. Chemical oocyte activation can significantly improve fertilization outcomes in cases with low fertilization rates or fertilization failure after ICSI using ejaculated sperm or spermatid from testis. In this paper, we reviewed the mechanisms of different chemical activators, and the application of chemical oocyte activation in micro-insemination with sperm and haploid spermatid.

Key words: Oocyte, Sprematid, Ethanol, Fertilization