ABSTRACT
Nowadays, the challenge of the cryopreservation, longterm storage, and successful implantation of the female gamete is feasible thanks to vitrification. There is a large population that is currently benefiting from oocyte banks, such as cancer patients who need an option for fertility preservation before undergoing potentially sterilizing treatment (1) or women who wish to delay their motherhood due to a variety of reasons (2, 3). Oocyte cryostorage brings additional advantages to assisted reproduction technology (ART) programs, being helpful in solving different clinical situations such as low-response patients (4), unpredictable availability of semen sample collection from the male partner, risk of suffering from ovarian hyper- stimulation syndrome (5), or some other cases in which embryo transfer is not advisable (6). Undoubtedly, ovum donation programs have also been major beneficiaries of egg banking. Oocyte cryostorage is very useful for over- coming the most common drawbacks involved in ovum donation as currently applied, such as synchronization between donors and recipients, long waiting lists subject to the availability of a suitable donor, and, most important, the absence of a quarantine period.
