Embryos not used in The existing cycle may be cryopreserved. Cryopreservation is often realized with vitrification, a immediate freezing procedure. Vitrification is assumed to forestall cryoinjury by decreasing the development of intracellular crystals.[35] All embryos may also be frozen in sufferers in danger for ovarian hyperstimulation syndrome (reviewed further in https://www.ivf.com.mx/