Cryopreservation of Human Embryos

Abstract

Principles of cryopreservation are similar for living cells.  The procedure of cryopreservation includes initial exposure to and equilibration with cryoprotectants, cooling to subzero temperatures, storage, thawing, and finally, dilution and removal of the cryoprotectants, with return to a physiologic environment that will allow further development. Cells must maintain structural integrity throughout the cryopreservation procedure. Major factors known to affect survival of cryopreserved cells include the species, the developmental stage, the cryoprotectants, and the method of cryopreservation.