Preserving eggs, sperm cells and fertilised eggs
Cryopreservation means “using the process of cooling to maintain viability”. Eggs, sperm cells and embryos can be frozen, e.g. using the vitrification process (glass-like) and can then be thawed at a later point in time. For instance, this enables the freezing of eggs and sperm cells before a chemotherapy treatment in order to be able to have a child after recovering. If a course of fertility treatment has produced several embryos, they can be frozen and used for another pregnancy later on.
Today, the vitrification process is regarded as the preferential treatment method. The extremely fast cooling (flash freezing) enables survival rates when thawing of 90 to 95%. The eggs therefore have a high degree of fertility, just like eggs that are not frozen. The same applies to embryos.