Ovarian Tissue Transplant Helps Cancer Survivors Maintain Fertility

A new study suggests that cryopreservation of ovarian tissue in female cancer survivors is an effective and safe way to maintain fertility.

Researchers at Rigshopitalet University Hospital (Copenhagen, Denmark), Aarhus University Hospital (Denmark), and other institutions conducted a retrospective cohort study of 41 women who received a total of 53 transplants of cryopreserved ovarian tissue between 2003 and 2014; mean age at time of cryopreservation was 29.8 years, and all but two of the women had an entire ovary cryopreserved. The women were followed with regular clinical visits after transplantation.

Once the ovarian tissue was transplanted back, the levels of follicle-stimulating hormone (FSH) and luteinizing hormone returned to normal after 4-5 months. One of the women, a prepubertal girl who was 13.8 years old at time of transplantation, succeeded in having puberty induced. The researchers found that the functional life span of the grafts has been greater than 10 years for two patients, greater than 7 years in 3 patients, greater than 4 years in 7 patients, between 2 and 4 years in 15 patients, between 1 and 2 years in 7 patients, and less than a year in 6 patients.

In all, 24 clinical pregnancies were established in the 32 women with a pregnancy-wish, with an overall 30% success rate. Of these, 10 succeeded in birthing one or more children, including one woman with a third trimester on-going pregnancy. In addition, two legal abortions and one second trimester miscarriage occurred. Three cancer relapses also occurred, but according to the researchers were unlikely to be due to the transplanted tissue. The study was published on August 24, 2015, in Human Reproduction.

“Many girls and young women who have been diagnosed with a disease such as cancer now have a realistic hope of recovery and living a normal life, but the treatment for their disease can cause infertility by damaging the functioning of their ovaries,” concluded lead author Annette Jensen, PhD, of the University of Copenhagen in Denmark, and colleagues. “Fertility preservation is increasingly becoming an integral part of treatment. However, as ovarian transplantation is still in its early days, its efficacy and safety need to be investigated.”

“Neither age at cryopreservation, age at first transplantation, amount of tissue grafted, nor the follicular density of the grafted tissue proved to predict successful conception,” added the researchers. “We hope that our results will enable this procedure to be regarded as an established method in other parts of the world, which has an important implication on how it is funded and reimbursed.”

Cryopreservation is a process wherein cells, whole tissues, or any other substances susceptible to damage caused by chemical reactivity or time are preserved by cooling to sub-zero temperatures so as to stop enzymatic activity. By default it should be considered that cryopreservation alters or compromises the structure and function of cells, unless it is proven otherwise for a particular cell population.

Related Links:
Rigshopitalet University Hospital 
Aarhus University Hospital