title: [Classification of human oocyte maturity].
abstract: Maturity of human oocytes was classified into five grades according to the appearance of the oocyte and the cumulus oophorus (Grade I-V). The relation between this "Grade" of oocyte and the state of fertilization was investigated and the following results were obtained. The proportion of fertilized eggs cleaving in vitro was higher when oocytes graded I or II were collected  than when oocytes graded III, IV or V were obtained (76% vs. 22%). When oocytes were aspirated from preovulatory follicles 26 hours after the onset of the luteinizing hormone (LH) surge 64% of them were Grade I or II. When oocytes were collected 36 hours after an injection of human chorionic gonadotropin (HCG), 88% of them were Grade I or II. Therefore it seems that the times chosen for oocyte recovery were appropriate. There was no correlation between the "Grade" of oocyte and follicle diameter or volume of follicle fluid.
mesh_terms: D004624:Embryo Transfer; D005260:Female; D005307:Fertilization in Vitro; D006801:Humans; D009865:Oocytes / Q000254:growth & development*; D010062:Ovulation Induction