Taking oral contraceptives (OC) for as little as 6 months offers significant protection against the risk of Ovarian cancer, a study shows.

“The implications of the findings are huge,” said Dr. Julia B. Greer.

“Ovarian cancer is the most fatal gynecologic malignancy and there is no good screening test for it,” she said. “Reproductive factors that have been shown to decrease risk, such as childbearing, hysterectomy, and tubal ligation, are not always within a woman’s control. Taking an oral contraceptive is an easy choice: there are numerous formulations, they are convenient, and insurance covers them for the most part.”

OC use has been consistently linked to a reduced risk of ovarian cancer in a dose-dependent fashion, but whether short-term OC use is protective remains controversial.

In their study published in the July 1st issue of the American Journal of Epidemiology, Greer, and colleagues from the University of Pittsburgh, looked at the association between short-term OC use and ovarian cancer in 608 “case” women who developed the disease and 926 cancer-free controls.

A total of 176 controls and 94 cases had used OC for less than 6 months. After adjusting for age and childbearing, the use of OCs for less than 6 months was associated with a significant reduction in Ovarian cancer risk.

This protective effect was only evident in short-term users who had stopped taking the pill because of side effects.

“The likely reason that the side effects were linked with a lower risk might be because the side effects themselves showed that the hormone level in the pill was high enough to suppress ovulation,” Greer told.

“Interrupting the cycle of continuous inflammation that comes along with ovulation has been shown to lower ovarian cancer risk,” she explained. “In other words, when a woman experienced side effects, the woman probably had normal ovulatory cycles and the pill was definitely working to keep her from ovulating.”

Summing up, Greer said: “If a woman does not have personal, cultural, or religious conflict with oral contraceptive use, and as little as 6 months may decrease your risk of developing a fatal disease, it seems like a logical choice to get a prescription sometime during those childbearing years.”

What we eat, whether we smoke or exercise regularly, as well as our contraceptive choices, are habits and behaviors that become pretty much set early in one’s life,” she said. “If we know that our choices could impact our health in the future, we could truly make informed decisions.”

SOURCE: American Journal of Epidemiology July 1, 2005.