"Talc is chemically similar to asbestos, which has been linked to ovarian cancer," said lead study author Dorota M. Gertig, MBBS, MHSc, ScD, senior research fellow at the Centre for Genetic Epidemiology, University of Melbourne, Australia. "Therefore, researchers have looked at the association between use of talc in the genital area and ovarian cancer."

Dr. Gertig and her colleagues used data on talc use prior to development of ovarian cancer, studying almost 80,000 women who responded to questions on talcum powder use in 1982 and were followed through 1996. The women were participants in the Nurses’ Health Study, a large, long-term study of 121,700 registered nurses in the US. The Australian researchers published their results in a recent issue of the Journal of the National Cancer Institute (Vol. 92, No. 3).

How the Study was Done

"We compared the incidence of ovarian cancer among women who had reported talc use and those who did not report talc use," Dr. Gertig said. "We also had information on other potential risk factors for ovarian cancer, such as never having had children, and we considered these factors in the analysis. One of the strengths of our study was that we asked women about use of talcum powder prior to development of ovarian cancer. In previous studies, women were asked about talc use after they developed ovarian cancer, and there was some concern that this may have biased the results."

Overall, the researchers found use of perineal talc was not associated with risk of ovarian cancer. This was true even for daily users of talcum powder. "However, we did find a modest increase in risk (about 40 percent) of a subtype of ovarian cancer," said Dr. Gertig. "Thus, there is a small possibility that using talcum powder in the genital area may increase the risk of a particular type of ovarian cancer."

Carmen Rodriguez, MD, MPH, senior epidemiologist at the American Cancer Society (ACS), calls the study "very well done," although it has limitations. "The researchers don’t know for how long and when the women used talcum powder," she said. "But one of this study’s strengths is the information on types of ovarian cancer. You would expect to find an increase in the serous type."

More Research is Needed

Dr. Rodriguez said the study’s conclusions are not enough to either prove or disprove the theory that talc use increases ovarian cancer risk. "It’s one more piece of evidence," she said.

Dr. Gertig also says it is premature to make recommendations regarding talc use. "Overall, our results are reassuring, as we did not see any increase in risk when we looked at all ovarian cancers combined," she said. "This refutes the findings of some earlier studies. The possibility of a small increase in risk for certain subtypes of ovarian cancer should be interpreted cautiously. Further study of specific subtypes is needed as well as biologic research on how talc might affect the ovaries."

Since 1973, the US government has required that all home-use talcum products be asbestos-free. These products include baby powders, body powders and facial powders.

The ACS estimates that there will be 23,1000 new cases of ovarian cancer in the US this year. Ovarian cancer accounts for 4 percent of all cancers in women and ranks second among gynecologic cancers, although it causes more deaths than any other cancer of the female reproductive system. An average woman’s lifetime risk of developing ovarian cancer is about 1.72 percent, or one in 58.