A critical first step in the eventual development of a technique to retain fertility in women with cancer who require treatments that might otherwise make them unable to have children has been completed by researchers funded by the National Institutes of Health.
The researchers have developed a method to advance undeveloped human eggs to near maturity, in laboratory cultures maintained outside the body. The technique focuses on the follicle, a tiny sac within the ovary that contains the immature egg. The researchers were able to grow human follicles in the laboratory for 30 days, until the eggs they contained were nearly mature.
The research seeks to provide women who require a fertility-ending treatment with options for reproduction after their treatment is complete. Men facing such treatments can freeze their sperm for use at a later date. Female cancer patients have fewer options. Unlike sperm, eggs rarely survive freezing and thawing.
The accomplishment represents the successful completion of the first of three steps needed to preserve a woman's fertility after radiation treatments or chemotherapy. For the next step, researchers will need to induce the egg's final division, so that it contains only half the genetic material of its precursors. Finally, the researchers will have to demonstrate that they can freeze and thaw human follicles before growing them in culture.
"The new technique could provide an option for women and girls who have cancer and are not yet ready to start families," said Duane Alexander, M.D., director of NIH's Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), which funded the research as part of the NIH Roadmap Interdisciplinary Research Consortium program. "An additional benefit is that it will allow researchers to more closely follow the process by which immature eggs grow and mature. In turn, these observations may lead to new advances for treating other forms of infertility."