2nd Step of IVF treatment: Oocyte Pick-up (OPU) and Microinjection (ICSI) Following ovarian stimulation step, the follicles preferably between 5-15 are grown and ready to be collected. HCG injection which triggers the maturation of oocytes is given at the end of the 1st step of IVF treatment. After 35-36 hours following HCG injection, the oocytes are collected under anesthesia. It takes about 15-30 minutes. A thin needle is introduced into the vagina and the oocytes are retrieved by puncturing each follicle. There is no incision in the vagina just a needle puncture is done. On the same day sperm is required and the selected sperm is introduced into each mature oocyte under a sophisticated microscope, this procedure is named as microinjection (ICSI). The next day, fertilized oocyte (by sperm) is named as embryo. Embryos are followed in the laboratory for 3-5 days. At the end od this follow-up the best embryo is selected and placed into the uterus. Banu Kumbak Aygün, M.D., Professor Obstetrics & Gynecology IVF and Endoscopic Surgery