Premier Medical CentreOocyte cryopreservation is a method to preserve fertility for young cancer patients. Its indications have been extended to include the quarantine and storage of donor oocytes in egg donation programs, women with medical conditions that may culminate in premature ovarian insufficiency, and women who wish to safeguard fertility decline associated with ageing. In this review, we discuss the history of oocyte cryopreservation and its various clinical applications, with a focus on the safety of the procedure for cancer patients, especially those with hormone-dependent cancers such as breast cancers. We also discuss ethical considerations for women who are cryopreserving their oocytes to protect against age-related fertility loss, the optimal age to undergo oocyte cryopreservation, and the optimal number of oocytes to freeze. The risks associated with the procedure and potential risks to children born from cryopreserved oocytes are also addressed.