Gamete preservation.

With the increase in survivorship following cancer for women in their reproductive years, as well as an increase in survivorship with childhood cancers, there is a demand for perfecting current fertility preservation methods and generating new options for patients who are unable to pursue the conventional course of fertility treatments. Cryopreservation using a slow-cooling method for embryos is currently the standard-of-care for women wishing to preserve their fertility; other options, such as oocyte cryopreservation and embryo vitrification, have become increasingly accepted methods of fertility preservation. As important as oocyte and embryo cryopreservation methods are for preserving fertility, some patients may be too sick or too young to undergo fertility treatments or have hormone-sensitive cancers that preclude standard approaches; therefore, other preservation options must be explored. Ovarian tissue cryopreservation followed by ovarian tissue transplant and follicle cryopreservation followed by in vitro follicle maturation are experimental techniques that have shown promising results. This chapter will discuss current methods of gamete preservation as well as new, experimental options to preserve immature gametes. An overview of ovarian biology, as well as the science of cryobiology, is discussed to help the reader better understand the circumstances under which different techniques may be used.