A US woman has had part of an ovary surgically transplanted into her body, after it was donated by her identical twin sister. Stephanie Yarber, aged 24, underwent premature menopause at the age of 13 - her ovaries stopped functioning and she became infertile. She and her husband have since tried a number of times to have a child. They have attempted IVF including two cycles using eggs donated by her twin sister, but without success. Her twin, Melanie, was not affected by premature menopause, and has gone on to have three children.
Doctors have been working on ovarian transplantation techniques for a long time. As with other forms of organ or tissue transplant, one of the main problems is rejection by the body's immune system. So transplanting ovarian tissue from an unrelated woman would require the use of immunosuppressant drugs, which may themselves affect ovulation and fertility. An identical twin, sharing the same genetic information, therefore, seemed like the ideal candidate to donate functioning ovarian tissue. In a five-hour operation, tissue was removed from Melanie's ovary and grafted onto Stephanie's. Ovarian tissue grafts have been attempted before, but usually using the patient's own tissue, removed and stored for later reimplantation, after cancer or other treatment that may affect fertility.
The team, led by Dr Sherman Silber at St. Luke's Hospital in St. Louis, Missouri, say the surgery went well and expect Stephanie's new ovaries to start ovulating within the next three months. Dr Silber, a fertility specialist at the hospital, said 'she can get pregnant any time after that and it will be a spontaneous pregnancy not requiring any medical treatment, Clomid, Nadatropin or IVF. Just a natural pregnancy, the old fashioned way'. Thanking her sister after the operation, Stephanie said 'we are very close. It takes a special person and Melanie - that's just who she is', adding 'she didn't even hesitate when I asked her about it'.
The medical team are also comparing the two sisters' DNA to see if a gene mutation may help explain why one had premature ovarian failure and the other did not. By studying both of them, it may be possible to find out why one became menopausal at 13 and the other did not. Dr Silber said that the women might give them clues as to the causes of some female infertility, adding 'with this extremely rare set of twins, it's an enormous opportunity to isolate and study the genes that supply eggs'.