STUDY OF THE OPTIMUM TIME FOR HUMAN CHORIONIC-GONADOTROPIN - OVUM PICKUP INTERVAL IN IN-VITRO FERTILIZATION

Objective: To study the optimum time for ovum pickup after human chori onic gonadotropin (ECG) injection in in vitro fertilization, Design: P rospective randomized study. Setting: The Egyptian IVF-ET center. Pati ents: Ninety couples with male factor infertility enrolled for intracy toplasmic sperm injection, divided into three groups. Ovum pickup was performed at 35 hr (group A), 36 hr (group B), and 37 hr (group C) aft er hCG injection. Results: Number of metaphase II oocytes was signific antly higher in group B compared to group A. There was no significant difference between group B and C. Fertilization rate was equal in all groups. The number of fertilized oocytes was significantly higher in g roup B as compared to group A, and there was no significant difference between groups B and C. Conclusion: Oocyte maturity in gonadotropin r eleasing hormone analogue agonist/human menopausal gonadotropin stimul ated cycles is attained 35 hr after hCG injection. Oocyte retrieval sh ould not be performed before 36 hr, and there is no risk of spontaneou s ovulation between 36 and 37 hr.