Fertilization and cleavage of the human ovumin vitro

Abstract
A method of cultivating and fertilizing human ova obtained from ovaries removed at operation is described. A special method of sampling active spermatozoa was used for fertilization. Zygote formation was observed 24–36 h after fertilization of the ripe ova, an embryo of the two-cell stage was formed after 36–40 h, and an embryo at the four-cell stage after 48 h. The number of blastomeres reached 8 after 60–64 h, and after approximately 100–120 h the embryos reached the morula stage. The results provide wide scope for the study of the physiology and pathology of early human embryonic development.