Belgian scientists have successfully transplanted ovarian tissue from a woman to her non-identical sister whose ovaries had been destroyed by chemo and radiotherapy. The tissue went on to produce healthy ovaries capable of producing eggs that when fertilized developed into embryos.
This is the first time such a procedure has been carried out successfully on sisters who are not identical twins. However, in this case the sisters are HLA compatible, which means the recipient sister’s immune system won’t attack the foreign tissue from her donor sister. HLA stands for human leukocyte antigen.
The case is described in the journal Human Reproduction and the procedure was carried out by Professor Jacques Donnez, of the Catholic University of Louvain in Brussels and colleagues.
In 1990, Teresa Alvaro, who was then 20 years old, had aggressive chemotherapy and radiotherapy followed by a bone marrow transplant to treat an inherited blood disorder known as beta-thalassemia major. The bone marrow donor was her then 17 year old sister, Sandra.
Unfortunately a side effect of the aggressive treatment was premature failure of Teresa’s ovaries.
In 2005, Teresa approached Prof Donnez to find out if it would be possible to restore the function of her ovaries with a tissue transplant. She said she did not want her sister to go through egg stimulating hormone treatment to donate eggs to her, and she wanted her own body to produce the eggs.
HLA compatibility between the sisters had already been established with the bone marrow transplant, so this was a big plus.
The two sisters were admitted to hospital in February 2006. Donnez and his team took small pieces of tissue (cortical fragments) from Sandra’s healthy ovaries, and immediately sutured them to the medulla in Teresa’s failed ovaries. Both procedures were performed by laparoscopy and the sisters were able to go home the next day.
Six months later, ultrasound and hormone tests showed that Teresa’s ovaries had started working again. Soon afterwards Teresa started menstruating and developed a follicle, a sign that egg production was probably taking place.
Eleven months after the transplant, the scientists detected two follicles which they pierced and from which they retrieved two mature eggs, or oocytes as they are called.
The eggs were inseminated with Teresa husband’s sperm and they produced two embryos, one developed to two cells and the other to three cells, but they did not grow any further and so were not reimplanted in Teresa’s uterus. The scientists said this was not unusual in IVF (in vitro fertilization) and that Teresa was planning to undergo further IVF cycles.
Donnez and colleagues concluded that as a result of “allotransplantation of fresh ovarian tissue” by laparoscopy between “two genetically non-identical sisters”, they were able to restore ovarian function after six months, and demonstrate “oocyte retrieval and embryo development”.
They said their work offers hope to young women facing premature failure of their ovaries and who have not had a chance to freeze their eggs, embryos, or ovarian cortex. The work also shows that if ovarian tissue is removed because of failure after cancer treatment for example, then it is important to leave at least one ovary intact, even if it is has stopped producing eggs, because it offers a potential site on which to graft donated ovarian tissue in the future.
“Allograft of ovarian cortex between two genetically non-identical sisters: Case Report.”
J. Donnez, M.M. Dolmans, C. Pirard, A.Van Langendonckt, D. Demylle, P. Jadoul, and J. Squifflet.
Hum. Reprod. Advance Access published on August 1, 2007.
doi: 10.1093/humrep/dem211
Written by: Catharine Paddock