There are now safe, successful techniques to preserve a woman’s fertility indefinitely.

Recent advances in cryopreservation make it possible to preserve female fertility for any length of time. It’s well known that for some years we have been able to preserve fertilized eggs, or embryos; we can freeze them indefinitely, then thaw the embryos at a later date, and achieve high pregnancy rates in IVF. It’s essentially a time-delayed IVF procedure, with a waiting period as long as you like, from when we retrieve and fertilize the egg, until we do the embryo implantation.

But for unmarried women, the trouble had previously been that this freezing process (although safe for embryos) destroyed unfertilized eggs, because eggs are so much more sensitive to freezing damage than embryos. If she did not have a husband yet and didn’t want anonymous donor sperm, the standard egg freezing procedures could do nothing for preserving her fertility… until now!

Ovarian Tissue Freezing and reimplantation, which Dr. Silber helped to pioneer, and egg vitrification pioneered in Japan, changed all that. An ovary could be removed from cancer patients before radiation and chemotherapy, frozen for some time, and then (3) returned to her body successfully after the cancer had been cured. The key realization was that all of the eggs in each ovary live only in the outermost layer of tissue, just 1 mm thick. The ready diffusibility of cryoprotectant into this thin layer, and the primordial immaturity of this storehouse of undeveloped eggs, allows ovarian tissue (and the eggs within it) to be frozen successfully. With the right microsurgical techniques, just this outer layer can be removed, frozen, and successfully grafted back on to the ovary at a later date, somewhat like a skin graft.