Delivery rate using cryopreserved oocytes is comparable to conventional in vitro fertilization using fresh oocytes: potential fertility preservation for female cancer patients

Objective: To explore the use of oocyte cryopreservation as a fertility-conserving option. Cancer treatments administered during the reproductive and adolescent years can result in sterility. Previous fertility preservation efforts focused on embryo rather than oocyte storage because the latter was deemed inefficient. Recently, several large reports of healthy births resulting from the transfer of embryos derived from frozen/thawed oocytes have been published. We sought to establish an oocyte cryopreservation program at our center. Design: Twenty-three oocyte cryopreservation cycles were performed. Collected oocytes were cryopreserved by either the slow or the vitrification method. Approximately 1-4 months later,a programmed cycle of thawing/warming, fertilization with intracytoplasmic sperm injection, and ET was performed; cycle and pregnancy Outcomes were assessed. Setting: University-based fertility center. Patient(s): Twenty-two infertile women. Intervention(s): Oocyte cryopreservation. Main Outcome Measure(s): Oocyte survival, embryo development, pregnancy outcomes. Result(s): Oocyte survival, 2-pronuclei fertilization, and blastocyst formation rates were 92%, 79%, and 43%, respectively. Fourteen women became pregnant; one miscarried; 10 have delivered 13 viable infants, and three pregnancies are ongoing for an ongoing/delivered pregnancy rate of 57%. This result was not statistically different from cycles performed consecutively in age-matched controls using fresh, nonfrozen autologous or donor oocytes during a similar time period. Conclusion(s): Oocyte cryopreservation appears to be a viable option for fertility preservation in some centers. (Fertil Steril (R) 2010;93:391-6. (C)2010 by American Society for Reproductive Medicine.)