Fertility & Cancer
Preservation Options for Both Men and Women
by Kutluk Oktay, MD, and Kenny Rodriguez-Wallberg MD, PhD
As cancer survival rates continue to improve, many young adults will face infertility after being cured from their malignant diseases. Fertility is a critical component of quality of life for cancer survivors. Given the significant impact of cancer treatments on fertility, fertility preservation should be a natural extension of cancer care.
Fertility preservation is an emerging discipline that addresses the need for improving cancer survivors’ options to have children later in life. Fertility preservation for women and men includes methods such as embryo, egg, sperm, and gonadal (ovarian or testicular) tissue freezing.
For an optimal chance in safeguarding fertility potential, these methods should be offered and performed before people with cancer start their chemotherapy or radiotherapy treatments. Therefore, a close collaboration between the oncology team and the reproductive medicine specialist is crucial. Unfortunately, at this time there is no evidence of any hormonal treatment (e.g., the administration of hormones that put ovaries to sleep) that could reduce the damage of cancer treatments on the eggs or on sperm germ cells. There are, however, agents in development, such as sphingosine-1-phosphate (S1P) agonists, which may be used in the future to pharmacologically block chemotherapy- and radiotherapy-induced germ cell death.
Fertility preservation requires a highly individualized approach involving both established and experimental techniques.
Fertility preservation is an emerging discipline that addresses
the need for improving cancer survivors’ options
to have children later in life.
Adult women with a partner may preserve embryos after undergoing ovarian stimulation and in vitro fertilization treatment. Embryo freezing is an established technique and is offered as a routine treatment in fertility clinics worldwide. For women with estrogen sensitive cancer, there are ovarian stimulation protocols with drugs that reduce estrogen exposure. The short-term follow-up of women who have been treated has not shown any detrimental effect on disease-free survival.
Dr. Kenny Rodriguez-Wallberg
Ovarian stimulation will take around two weeks and has to be started at the beginning of a menstrual cycle. Hence, a two- to six-week period of delay may be required. This may be a limitation for some women who need to start their cancer treatments immediately. Luckily for most women with breast cancer, chemotherapy does not have to be started for six to eight weeks after breast surgery, which would give plenty of time to complete one to two cycles of ovarian stimulation for embryo or egg freezing.
For single women, there is the option of egg freezing. As the maturation of the eggs at the laboratory is still under development, the women need to undergo stimulation with hormones as with IVF, and a delay of at least two weeks may also be necessary. In the early 2000s, the pregnancy rates were still poor after fertilizing frozen-thawed eggs, but with the modern freezing technologies, IVF success rates with frozen-thawed eggs have improved. They are now closer to the success rates of standard IVF techniques utilizing fresh eggs. Nevertheless, the technique is still experimental, and larger studies with long-term followup of children born from egg freezing are needed.
Another experimental option is ovarian tissue freezing for future transplantation. This procedure does not require ovarian stimulation and can be performed at any time during the menstrual cycle. Ovarian tissue harvesting is performed by an outpatient laparoscopy, and the frozen tissue can later be transplanted in the pelvis at the original place or at other locations.
Ovarian tissue freezing is the only viable option in young girls, women for whom hormone stimulation is contraindicated, and women who need to start cancer treatment with no delay. It is also the only option for pre-pubertal girls. Hundreds of women have undergone ovarian tissue freezing, but only a small fraction has returned for ovarian transplantation. A recent international survey identified 25 reports of ovarian transplantation. Out of 56 cases of transplants (including those done with unfrozen tissue), nine pregnancies in eight women at 12 months were identified, giving a cumulative pregnancy rate of 37 percent.
The question of who should be offered fertility preservation is at times difficult to answer, as studies have focused on suppression of menstrual cycles and not fertility after cancer treatments. Since younger women will have a larger reserve of eggs, they may continue to menstruate for some time and conceive even after a very aggressive chemotherapy regimen, but their fertility may be severely impaired. Furthermore, each person’s situation is unique. A 25-year-old woman may still need fertility preservation if she plans to have a large family and is undergoing a cancer treatment that might potentially remove 10 years of her reproductive life. If, on the other hand, she is only interested in having one child, she may not need further treatment.
Adult males and young male adolescents can prevent infertility by sperm banking before starting their cancer treatments. Sperm freezing has been shown to be highly successful, and many children are born after fertility treatments using frozen-thawed sperm. Even a single ejaculate is sufficient. With the advent of intracytoplasmic sperm injection (ICSI) techniques (IVF with ICSI), each viable sperm can be put to use. In pre-pubertal boys, ongoing studies on testicular tissue freezing are being conducted, but no clinical success has yet been reported.
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Dr. Kutluk Oktay is professor of Obstetrics & Gynecology and director of the division of Reproductive Medicine & Infertility at New York Medical College – Westchester Medical Center in Valhalla, NY, and medical director of the Institute for Fertility Preservation in New York, NY. For more information about the Institute, visit www.fertilitypreservation.org. Dr. Kenny Rodriguez-Wallberg is the head of the Fertility Preservation Program at Karolinska University Hospital Huddinge in Stockholm, Sweden.
This article was originally published in Coping® with Cancer magazine, May/June 2009.