Pediatric Fertility Preservation Program

Oocyte (egg) and embryo freezing

Ovarian stimulation for the purpose of harvesting and freezing eggs is a well-established way of preserving fertility in post-pubertal females. Because this process often delays the start of treatment, it is not an appropriate option for every patient. When a patient’s primary care team feels this can be safely done, hormonal medication is used to stimulate the formation of multiple follicles in the ovary, which contain eggs. These eggs are then removed in a minor surgical procedure and are frozen for the patient’s potential future use to achieve a pregnancy.

There have been hundreds of live births from frozen eggs. In a circumstance where a young adult patient has a partner or wishes to use donated sperm, there is also the option of using the eggs to create an embryo, which can be frozen for future use. Embryo freezing is considered an established method of fertility preservation.

Ovarian tissue cryopreservation

Ovarian tissue freezing is available for all ages including young girls that have not yet gone through puberty. The advantage of ovarian tissue freezing is that the procedure can be done quickly and does not require time to stimulate eggs in the ovary with medication. Ovarian tissue freezing also requires a surgical procedure. In this process, doctors surgically remove an entire ovary. The tissue is then processed, frozen, and stored for future use. When the patient wishes to become pregnant, the tissue can be thawed and re-implanted. After transplants, the tissue starts producing hormones and eggs.

There is also active research in extracting immature eggs from ovarian tissue in the laboratory and maturing them for use in in-vitro fertilization, without re-implanting the tissue. So far, successful pregnancies have only occurred after re-implanting the tissue. However, in the future it may be possible to have a pregnancy without having to have the tissue re-implanted. While ovarian tissue cryopreservation holds a lot of promise, it is still considered experimental.