Cryopreservation and culture of human primordial and primary ovarian follicles

Cryopreservation of ovarian cortical tissue containing high numbers of prim ordial and primary follicles would benefit young women who are going to und ergo chemotherapy or radiotherapy, or anticipated premature ovarian failure . Human ovarian tissue has been successfully cryopreserved using dimethyl s ulphoxide, propanediol and ethylene glycol as cryoprotectants. The viabilit y after thawing has been shown morphologically, using viability tests, by t ransplanting the tissue to immunodeficient mice, and by culturing them in v itro. Maturation of oocytes in in vitro cultures from early follicles would be better than replantation for girls with malignancies which could be rep lanted with the tissue. For the time being we have managed to culture cryop reserved human primordial and primary follicles to secondary, and occasiona lly to early antral stages in organ culture within slices of cortical tissu e in extracellular matrix. The culture conditions have to be improved to ge t systematically early antral follicles for a second step of maturation of cumulus-oocyte-complexes. (C) 2000 Elsevier Science Ireland Ltd. All Sights reserved.