This chapter summarizes the technical challenges that had to be overcome for the freezing/thawing of intact ovaries with animal experiments first and then with humans. Two main problems with whole organ cryopreservation and re-transplantation have caused technical difficulties: the first related to the feasibility of executing a perfect vascular re-anastomosis of the whole organ with re-establishment of a prompt vascular flow; the second related to the development of a successful cryopreservation protocol. To improve the technique of freeze-thaw and transplantation of whole ovaries, adult female sheep have become the preferred animal model to study both slow cooling and vitrification methods. In the future, patients with malignancies at high risk of ovarian metastasis could have a whole ovary removed and perfused in vitro, to stimulate folliculogenesis in vitro. If successful, oocytes could be harvested for cryopreservation or for fertilization and subsequent embryo cryopreservation.

This chapter reviews the progress in cryopreservation and transplantation of whole ovaries that have been made in both animal and human models. The rodent model and the sheep model are the two animal models discussed in the chapter. Whole ovary cryopreservation in the sheep has been attempted through both slow-cooling and vitrification methodologies. The chapter describes successful cryopreservation of the human ovary in two premenopausal women. In each case, one ovary was harvested and perfused. Another area of continued refinement in whole organ cryopreservation and subsequent transplantation is the method of oophorectomy. Laparoscopy has been shown to be successful in resection of the ovary and pedicle, and the advent of robotic surgery will continue to aid in the long dissection of the vascular pedicle that is a prerequisite both for perfusion of the ovarian artery and for a future anastomosis.