In the News Cold Comfort: Young Women with Cancer Can Freeze an Ovary to Keep Kids in the Picture - Scientific American
Cold Comfort: Young Women with Cancer Can Freeze an Ovary to Keep Kids in the Picture - Scientific American
by Katie Moisse
Before starting cancer treatment, one walnut-size ovary is removed in a 30-minute, minimally invasive laparoscopic procedure. The tissue is then cut into pieces the size of rice grains and flash frozen in liquid nitrogen at temperatures nearing –200 degrees Celsius by a process called vitrification [video].
After the treatment regime is completed, should the survivor choose to become pregnant, the tissue is thawed and re-implanted [video] onto the surface of the remaining ovary or the ligament next to the fallopian tube. Four months later—the time it takes for thawed primordial follicles (the functional units of the ovary) to mature and start ovulating—the survivor can conceive without hormones and in vitro fertilization, making the procedure a "natural" and effective way to preserve fertility in young women and girls with cancer, says Sherman Silber, director of Saint Luke's Hospital's Infertility Center of Saint Louis.
"Five to 10 years down the line these women are going to want to have babies, even though when they're 19 they're only thinking about their cancer," Silber says. Whereas childbearing might not be on the minds of these girls and young women, eager to start their therapy, this quick procedure can keep kids in the picture without interfering with the fight to survive. "We just take out the ovarian tissue and two days later they can start their treatment," Silber says.
Although the procedure is still relatively new, Silber insists that it is no longer experimental. Nine babies have been born to women who had prematurely stopped menstruating (not all cancer survivors) and later received frozen ovarian tissue implants in his clinic.
But Silber thinks all young patients beginning certain cancer treatment regimes should freeze ovarian tissue regardless of the model. "These young women do lose their fertility. They do become menopausal," Silber says. "Maybe they do hit menstruation, but they do go into menopause early. Up to 90 percent of young women with cancer will lose their fertility from the treatment that cures them."
The procedure costs roughly $4,000, according to Silber, an expense that he says should be (and usually is) covered by health insurance providers. "Insurance is paying $200,000 for cancer treatment; $4,000 isn't too much to preserve fertility," he says.
In the early days of the procedure (about five years ago) the frozen ovarian tissue was re-implanted under the skin of the forearm (for ease of egg retrieval) where it became revascularized and, under stimulation, resumed its natural role producing eggs, despite the very unnatural environment. The eggs would then be collected from the arm and fertilized in vitro. But Silber says that re-implanting the tissue [video] at the ovary site where it belongs using microsurgical techniques allows the woman to conceive naturally.