Ovarian tissue cryopreservation and transplantation: It is a noble goal for mammalian species?: A review

Ovarian tissue cryopreservation and transplantation is a noble goal for humanity and preserving the genetic materials of superior animal species. Females facing chemotherapy and radiation treatment are exposed to gonadal damage. In addition, superior animals due to sudden death or aging are also at risk to lose their genetic materials. Ovarian tissue cryopreservation and transplantation has been successfully carried out in different mammalian species resulting in formation of ovarian structures and outcomes upon pregnancy. Trials were applied over ovarian cryopreservation and re-transplantation in humans and different animal species. Several factors effect on ovarian cryopreservation and re-transplantation including technical aspects of freezing ovarian tissue, size of ovarian tissue, age of female, location of transplantation, auto- and xenotransplantation. Restoration of ovarian follicle growth and development, ovulation and corpora lutea formation and development were confirmed in several studies. The growth and development of ovarian follicles to pre-ovulatory follicles and corpora lutea in mammals lasts several months. In addition, in vitro maturation of oocytes aspirated from transplanted ovarian tissues were confirmed in addition to their further embryonic development. Therefore, this review is carried out to collect and discuss the ovarian tissue cryopreservation and transplantation and its effects on both humans and animals as well.