USC Fertility

Embryo Freezing

Embryo freezing is a proven, successful process that dates back nearly 20 years.

The gametes of both parents are united in an early stage embryo which then undergoes a computerized precise freezing process in which its temperature is lowered to that of liquid nitrogen (-196°C). No biological activity takes place at this temperature, and therefore, the embryos do not lose any viability over time (even many years) and may be thawed at any time that the patients choose.

During the Cryopreservation process, however, some 20% of embryos endure sufficient trauma to prevent further viability upon thawing. Among the 80% of embryos that survive, individual implantation rates are approximately two-thirds of these that have not previously been frozen.