For successful pregnancy, the sperm and egg released from the ovary must unite together. This process is termed as fertilization and this occurs within the fallopian tube, which joins the uterus (womb) to the ovary. However, with the process of IVF, the union occurs in the laboratory, after the egg and sperm have been collected and cultured together in order to form an embryo thereafter which is transferred to the uterus for the growth.