Presently, oocyte cryopreservation (egg freezing) is considered to be the “conventional” fertility preservation technique. In some cases, however, it isn’t an option (for example, due to medical reasons), so alternative methods, such as ovarian tissue freezing are used.
What is ovarian tissue freezing?
Ovary freezing is a relatively new technique, where doctors laparoscopically remove an ovary (or part of one) and then cryopreserve it with the intention of transplanting it back at a later date. Designed to help women who were diagnosed with cancers and couldn’t undergo egg freezing (either due to time constraints or the nature of their disease), it was first used in 1999 but is still considered experimental.
A recently concluded study, conducted by the technique’s inventor Kutluk Oktay together with Dr. Fernanda Pacheco, which examined data from 1999 to 2016, has at last given more clarity about it.
Key findings, published in the Reproductive Sciences journal, were:
- 84 babies were born to 309 women who underwent the procedure (37% success rate).
- The average age of ovary freezing for women who went on to conceive was 27. It should, however, be noted that ages were recorded in only 113 cases.
- Following reimplantation, menstrual cycle restarted in almost two thirds of the patients.
- Of women who fell pregnant, most did so naturally; about a third required IVF.
Based on these results, researchers believe ovarian tissue freezing is a better option than “traditional” egg cryopreservation, because it holds the promise of an IVF-free pregnancy and can also reverse menopause. They now intend to investigate whether it can help healthy women who wish to delay starting a family, similarly to “social freezing”.