Numerical Simulations Demonstrate Safe Vitrification and Warming of Embryos Using the Rapid-i™ Device

Magazine article, 2009

During cryopreservation of human embryos, ice crystal formation in the embryos or in surrounding media may cause cryodamage to them and can be lethal. A strategy to avoid this is the vitrification procedure when the embryo and the surrounding medium undergo the transition to glassy state rather than a crystalline one during cooling. Similarly, recrystallization in the embryo or the medium must be avoided during the warming process. The necessary conditions for this are rapid cooling and warming rates. We assess the cooling and warming rates in the Rapid-i™ device for vitrification and cryostorage of human embryos from Vitrolife Sweden AB with help of numerical simulations. We demonstrate that the fast cooling and warming rates necessary for safe vitrification and warming are achieved in the device. We also determine safe margins for the warming procedure.