The benefits of physical activity do not extend to reducing the risk of developing ovarian cancer, according to a new study reported in the International Journal of Cancer.

“However, despite not protecting for ovarian cancer, physical activity has so many other positive health effects that women should be encouraged to exercise daily, if possible,” study chief Dr. Elisabete Weiderpass from the Karolinska Institute in Stockholm emphasized in comments to Reuters Health.

She and her colleagues assessed associations between physical activity during different periods of life and ovarian cancer incidence in roughly 96,000 women from Norway and Sweden who were followed for more than a decade.

“We asked the women how much they exercised at ages 14, 30 and between ages 30 and 50 year,” Weiderpass said.

A total of 264 women developed ovarian cancer during the time they were followed.

According to Weiderpass, “the risk (probability) of developing ovarian cancer was the same for women who were highly active or sedentary, in any period of life.” The results were similar for different ovarian tumor types and for different subsets of women grouped according to known risk factors for ovarian cancer.

“We concluded that physical activity does not protect women for ovarian cancer,” Weiderpass said. She acknowledged that this was a bit of a surprise. “We thought that physical activity would protect women from ovarian cancer,” she said.

SOURCE: International Journal of Cancer, June 15, 2006.