Abstract: The present invention relates to the cryopreservation and preparation of warmed oocytes for fertilization. Cryopreservation of oocytes using vitrification methods is disclosed. Exemplary techniques include making a vent in the zona pellucida surrounding the oocyte; contacting the oocyte with a vitrification solution comprising at least one cryoprotectant; and vitrifying the oocyte. Further methods of warming the vitrified oocyte, in preparation for intracellular sperm injection are disclosed, allowing for the assessment of successful fertilization.