(RxWiki News) Young women who require chemotherapy or other cancer treatment may find that the treatment risks permanent damage to their fertility - but science is catching up.
In addition to freezing their eggs or embryos prior to cancer treatment, an additional option showing success involves preserving tissue samples from women's ovaries.
These tissues can be later surgically sewn back into the women, potentially reinstating the function of their ovaries.
"Talk to your doctor about preserving your fertility before cancer treatment."
Dr. Gianluca Gennarelli, of Clinica Universitaria Sant'Anna in Turin, Italy, described a case at a recent fertility conference in which a woman was able to successfully preserve her fertility with this method despite seven years between the initial biopsy to remove the ovarian tissue and the procedure to return it to her body.
The case study involved a 21-year-old patient who would be receiving a high dose of chemotherapy and a bone marrow transplant. First, however, she saw a fertility doctor to see if it may be possible to preserve her ability to have children in the event that her chemotherapy ravaged her ovaries.
With a surgical procedure called a laparoscopy, the surgeons collected tissue samples from both ovaries, slowly froze them and stored them in liquid nitrogen, a method called "cryopreservation."
The chemotherapy regimen did lead the patient's ovaries to fail. Seven years later, after the patient had beaten the cancer and recovered, she wanted to find out whether her fertility could be restored with the pieces of her ovaries that had been frozen.
The surgeons thawed 32 fragments of ovarian cortical tissue and grafted them to parts of her ovaries. After two months, her ovaries began to work and released eggs in at least six menstrual cycles.
Fifteen months after the tissue had been grafted to her ovaries, the patient became pregnant, and she delivered a healthy baby in March 2012.
Based on known cases, the child was the 22nd baby to be born following the reinstitution of a woman's fertility with this freeze-thaw-graft method, first successfully done eight years ago.
The advantage of this method over other methods of preserving a woman's fertility before cancer treatment is that it can be done immediately and does not require a woman to take hormones or go through an entire menstrual cycle.
Other ways of preserving a woman's fertility prior to cancer treatment include more standard procedures used in IVF, or in vitro fertilization, during which the woman receives hormones to stimulate her ovaries to release multiple eggs.
Then the eggs are frozen, or they are first fertilized if the woman has a partner and then the embryos are frozen in storage.
However, storing eggs or embryos may not be possible if a woman needs immediate treatment that can't wait for a full menstrual cycle or if her cancer could be made worse by the hormones necessary to induce the release of her eggs.
The disadvantage of the method used with this patient - where pieces of the ovaries themselves are surgically removed and stored - is that it simply doesn't have a long track record of success yet, partly because it is considered experimental and is not done as often.
"We and other groups now believe that ovarian tissue freezing for fertility preservation should not be considered experimental but be recognized as a routine clinical practice to be offered in appropriate cases," said Dr. Gennarelli.
Dr. Gennarelli said that one additional reason there may not have been many babies born using this method of preserving and re-grafting ovarian tissue is that not as many women may be taking advantage of the opportunity to preserve their fertility or to explore pregnancy options after cancer treatment.
"The reasons are probably many, but the simplest might be that not so many patients have reached the age or the decision to conceive," he said.
Dr. Gennarelli said that they have not so far been able to determine whether there are any "time limits" on how long the ovarian tissue can be frozen.
The study was presented July 4 at the 28th annual meeting of the European Society of Human Reproduction and Embryology in Istanbul.
Because the study has not yet been published in a peer-reviewed journal, its results should be regarded as preliminary and still require review by researchers in the field. No information was available regarding funding or disclosures.