Cryopreserving human embryos is important in fertility treatments. Vitrification, a fast freezing method, is now preferred over slow freezing. A study at a university clinic showed that vitrifying human zygotes led to high survival rates and better pregnancy outcomes compared to slow freezing. Out of 849 zygotes frozen, 89% survived thawing. The pregnancy rate with vitrification was 36.9%, three times higher than with slow freezing. Vitrification is a successful and reliable method for preserving human embryos.