Cryopreservation of embryos
Freezing embryos is the most widely available and established way of preserving fertility before cancer treatment. The process involves retrieving eggs from the ovaries during an outpatient procedure, fertilizing them in the laboratory with sperm from a partner or donor, and freezing them for later use. A woman will undergo a 2 week regimen of hormone shots to develop multiple eggs before her therapy. In younger women, a dozen or more eggs may be collected.
The first successful pregnancy from a frozen human embryo was reported in 1983, and the technology has resulted in hundreds of thousands of babies.