Hawaii Researchers Found Birth Control Pills Reduce Ovarian Cancer

HONOLULU (KHNL) -- Researchers at the Cancer Research Center of Hawaii have found that even short-term use of oral contraceptives effectively cut ovarian cancer risk over decades.

The researchers collected data in Hawaii and Los Angleles from more than 800 women with ovarian cancer diagnosed in 1993 to 2006 and more than 900 women without cancer.

They found that OC user reduces epithelial ovarian cancer risk after a short time since first use, has a long-lasting effect and does not depend on the age of the user.

The risk for recent OC users of five years or less was 81% lower than in women who never used the pill.  The reduction in risk was 36% among women who stopped using the pill 20 or more years ago.  On average, contraceptive use provided a 5% reduction in risk per year of use.

The mechanism for the protective influence of OC against ovarian cancer remains unclear.  Researchers believe one hypothesis is that high levels of hormornes during pregnancy and sterioidal contraceptives use leads to the clearing of cancerous ovarian cells.

The results of their study were published in the March 2008 issue of the journal Epidemiology.