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Oocyte cryopreservation is an important method in the field of infertility. This procedure can benefit the cancer patient wishing to preserve fertility before initiation of any destructive chemotherapy or radiation therapy. It is a substitute for embryo cryopreservation and thereby avoids associated ethical issues. Oocyte cryopreservation technology can lead to the establishment of "oocytes banks" and provides solutions to ovarian failure patients. Technical obstacles were the main cause for the slow progress of oocyte cryopreservation. When compared to embryos and sperm cryopreservation technologies which are in common use worldwide, the reports on oocyte cryopreservation-derived pregnancies, were sporadic and with low success rates. However, in recent years we are witnessing more and more publications and increasing success rates in this important and fascinating field. Improvement in the freezing protocols and the introduction of vitrification procedures increased the survival rates and led to the birth of more then 100 healthy newborns. In the future we believe this method will be part of daily work in the fertility world. This review describes the methods available today and the clinical reports published in this field.

In vitro maturation is a new and promising technique in the field of artificial reproductive technology. This method provides an alternative treatment to the known treatments and a solution for one of the most common and disturbing problems of infertility treatment, the hyperstimulation syndrome. The method is particularly useful in cases of patients with polycystic ovarian syndrome. The physiological process of oocyte maturation requires maturation of the nucleus and maturation of the oocyte cytoplasm. In the process of in vitro maturation of the oocyte, oocytes in their late stages of maturation are aspirated from the follicles and transferred to specific culture conditions to achieve complete maturation. The process of oocyte retrieval from small and undeveloped follicles needs proper equipment and experience. Therefore, this process requires deep understanding of the physiological process of oocyte and follicles growth and maturation, proper equipment and especially good experienced laboratory support. This review aims to describe the physiological basis for the process, the recommended protocols and to report the experience published so far on success rates and treatment safety, both maternal and fetal.