Ovarian Transplantation: Pioneer in Ovarian Transplant Gives Birth to Her Second Child

What is ovarian transplantation and why is it done?

It is common after breast cancer treatment and even more frequent after the intense treatment cycles that prepare patients with leukemia for a life saving bone marrow transplant.

Additionally to the direct effects of not being able to bear children, and undergoing menopause prematurely, cancer treatment induced infertility after a successful cancer treatment can seriously jeopardize the emotional wellbeing of the cancer survivor. Ovarian transplantation can be a solution for this problem. The principle is similar to autologous bone marrow transplants which are sometimes used to allow an extremely strong cancer treatment that has the potential to kill all of the bone marrow. In contrast to allogeneic bone marrow transplantation, in which bone marrow from a donor is infused into the patient  after the cancer treatment of the patient has been done, in autologous bone marrow transplantation, bone marrow of the patient is harvested before the cancer procedure and stored by cryopreservation. This means it is frozen in a special solution using a special process, that allows tissue to stay alive through the freezing and thawing cycle. After the cancer treatment the patient is given his or her own bone marrow back which will grow like before. Because it is the patient’s own tissue, immune suppressive medication that is vital for other transplantations to keep the body from rejecting the foreign tissue, is not necessary.

In ovarian transplantations, a piece of ovary tissue is surgically removed from the woman before she undergoes a cancer treatment that has a high risk of rendering the ovary non-functional. The ovary tissue can be frozen by either of two procedures: slow freezing or vitrification which is extremely fast freezing. Recent research suggested that the vitrification has a higher success rates after transplantation of the thawed tissue. Since monozygotic (identical) twins share all their genes, they have the additional option of donating ovarian tissue to one another. Tissues transplanted between identical twins are not recognized as foreign tissues, but the recipient’s body considers it instead to be her own tissue. 

Transplantations of ovarian tissue between unrelated donors much like kidney transplantations are in theory possible. However, since the recipient would recognize this tissue as foreign, just like in kidney transplantation, the patient would need to take strong immunosuppressive medication to not reject the tissue. These medications, however, cause many severe side effects, which are acceptable in the case of kidney, liver, or heart transplants, as organ failure would be life threatening. In the case of ovarian transplantation, the risk of the side effects outweigh the benefits of this potential procedure, and it is therefore not an option for women who underwent menopause prematurely for other causes than a scheduled cancer treatment.

Autologous ovarian transplantation is only an option, if healthy ovarian tissue was harvested before the procedure that caused infertility. It is also theoretically possible to use ovarian transplantation to extend the fertile time before menopause during the life of a woman, if tissue is harvested from the women in her twenties. It can then be stored frozen long enough to be able to implant it, when the woman is in her forties to increase her fertile age. However storage of frozen tissue is expensive and thus far, ovarian transplantation has not (yet) been done to avoid biologically timely menopause.

Read More: Premature ovarian failure

When a pioneer in ovarian transplant became pregnant again and gave birth to her second child

Stinne Holm Bergholdt who works at the University of Southern Denmark in Odense was rendered infertile through cancer treatment. Before her cancer treatment, ovarian tissue was removed and frozen. In 2006, an ovarian transplantation using a part of the frozen tissue was done. Even now,  there is still frozen tissue preserved in liquid nitrogen that might stay functional for up to forty years. The transplanted ovary tissue began to work properly within a few months. She conceived a baby through in vitro fertilization. In vitro fertilization involves the removal of a few mature eggs after a cycle of hormone treatments that induce the maturation of the eggs. The fertilization of these eggs is done in vitro which means in it is done in a test tube. The fertilized eggs were then implanted in the uterus of Ms. Bergholdt and in 2007 she gave birth to a healthy baby girl. Ms. Bergholdt wished to have another child and was ready to undergo the same treatment again. However, when she went to the specialist to start the hormone treatment necessary to induce the maturation of new eggs, to her surprise, she found out that she was pregnant. The baby was conceived completely naturally. Another healthy baby girl was delivered in September 2008. While other cases of natural conception after an ovarian transplant are known, Ms. Bergholdt‘s case is the first time that two consecutive successful pregnancies occurred after an ovarian transplantation.

Ms. Bergholdt who is 32 is also one of the authors on the publication about this pregnancy. According to her treating physician Professor Claus Yding Andersen, her experience with giving birth twice after ovarian transplantation with one of the babies conceived naturally shows that ovarian transplantation is a viable treatment option for premature, cancer treatment induced infertility.