Fresh ovarian tissue and whole ovary transplantation.

A series of monozygotic (MZ) twin pairs discordant for premature ovarian failure presented an unusual opportunity to study ovarian transplantation. Ten MZ twin pairs requested ovarian transplantation and nine have undergone transplantation with cryopreservation of spare tissue. Eight had a fresh cortical tissue transplant, one of whom received a second frozen-thawed transplant after the first ceased functioning at 3 years. One had a fresh microvascular transplant. All recipients reinitiated ovulatory menstrual cycles and normal day 3 serum follicle-stimulating hormone levels by 77 to 142 days. Seven have already conceived naturally (three twice). Currently, seven healthy infants have been delivered out of 10 pregnancies. The oldest transplant ceased functioning by 3 years, but then she conceived again after a frozen-thawed secondary transplant. There was no apparent difference in return of ovarian function between the nine fresh ovarian grafts and the one frozen graft. Ovarian transplantation appears to restore ovulatory function robustly. Ten pregnancies, leading to seven healthy infants, including one after cryopreservation, bode well for application to fertility preservation.