Survival of human oocytes cryopreserved with or without the cumulus in 1,2-propanediol

Abstract
Although cryopreservation of human preembryos has been carried out with success, the cryostorage of oocytes, which pose fewer controversial moral, ethical, and legal problems has been much less successful. Various attempts to cryopreserve human oocytes have been mostly unsuccessful and the search for an optimal protocol for oocyte cryopreservation remains elusive. We therefore undertook this study to determine the effect of oocyte cryostorage in 1,2-propanediol.