COPENHAGEN — The recent announcement of two births made possible by ovarian transplant procedures marks a new stage in the field of fertility restoration, raising ethical questions about whether such procedures should be made more widely available, according to Anthony Rutherford, M.D.
“Is it ethical now to start storing ovarian tissue for patients? Is this still experimental research or is it established clinical practice?” Dr. Rutherford, a consultant gynecologist at Leeds (England) General Infirmary, asked during a presentation at the annual meeting of the European Society for Human Reproduction and Embryology.
Experts in the field of ovarian transplant are divided about how the technology should be applied and who should undergo the procedure.
The majority of work in this area has focused on women who are about to undergo aggressive chemotherapy, which generally leads to infertility. These patients freeze their healthy ovarian tissue before having chemotherapy. Once their cancer is in remission, they can have small pieces of their ovarian tissue transplanted into them, a procedure known as autotransplantation.
This was the case with a 28-year-old Israeli woman who gave birth at the end of June after ovarian transplantation followed by in vitro fertilization (IVF), reported Dror Meirow, M.D., of Sheba Medical Center in Ramat Gan, Israel (http://content.nejm.org/cgi/reprint/NEJMc055237v1.pdf
A few weeks earlier, a baby was born to a 24-year-old U.S. woman with no history of chemotherapy (N. Engl. J. Med. 2005:353;58–63). This woman had experienced premature ovarian failure at age 14. Instead of receiving an autotransplant of her own ovarian tissue, she was the first recipient of an ovarian allograft, receiving tissue from her identical twin.
The choice by her surgeon, Saint Louis-based Sherman Silber, M.D., to extend fertility restoration beyond the realm of chemotherapy patients, to move from autotransplantation into allotransplantation, and to use a groundbreaking transplant technique, raises the question of opening access to such techniques to a wider population of women—and for more diverse reasons.
Until now, transplant efforts aimed at restoring ovarian function and ovulation have required IVF to achieve a pregnancy. But Dr. Silber's technique has eliminated the necessity of that expensive procedure, achieving the world's first human orthotopic ovarian transplant that allowed natural conception.
(The birth of a Belgian baby last year following an orthotopic ovarian transplant procedure and natural conception was questioned by some experts, since it could not be confirmed that she had ovulated from the transplanted ovarian tissue [Lancet 2004:364;1405–10]. Since her ovaries had been left in place, spontaneous ovulation could not be ruled out.)
From the points of view of Dr. Silber's sibling patients, ovarian transplant is a minimally invasive outpatient procedure—possibly giving the recipient years of potential for spontaneous conceptions.
Dr. Silber said that he believes the appeal of this more patient-friendly ovarian transplantation could be wide reaching, extending beyond autotransplants for chemotherapy patients and even beyond allotransplants for patients with premature ovarian failure. Dr. Silber has performed two additional ovarian transplants in two other twin sets since his first success, but to date there are no pregnancies.
He has already had requests from general infertility patients for allotransplants as an alternative to egg donation. (Some couples say they have no other choice for religious reasons.)
Dr. Silber said he sees the appeal of ovarian transplant extending to the general population who might choose ovarian tissue freezing and subsequent autotransplantation in the hopes of extending their biological clocks.
Dr. Rutherford expressed caution with regard to these advances. “We certainly need to be very careful about the patients that we select,” he said in an interview, adding that he feels it is premature to offer ovarian transplant for social rather than medical reasons.
And even for those patients who have medical reasons for wanting ovarian transplant, many physicians, including Dr. Rutherford, are hesitant to embrace the procedure as a routine clinical practice. “Are we giving false hope to vulnerable patients?” he asked.
Dr. Rutherford has called for the creation of a registry to keep track of all ovarian transplant cases and to follow them to assess the efficacy and safety of the procedure.