Risk of Ovarian Cancer in Relation to Estrogen and Progestin Dose and Use Characteristics of Oral Contraceptives. SHARE Study Group. Steroid Hormones and Reproductions
Roberta B. Ness, Jeane Ann Grisso, Jennifer Klapper, et al.
Abramson Cancer Center of the University of Pennsylvania
Last Modified: November 1, 2001
Reviewers: Li Liu, MD
Source: American Journal of Epidemiology, Volume 152:233-241, (August) 2000
Précis: Low-dose oral contraceptives appeared to be effective in reducing ovarian cancer risk
IntroductionThe risk of ovarian cancer can be reduced by 50% or more in unselected women with long-term use of oral contraceptives (Am J Epidemiol 1992 Nov 15;136(10):1184-203). An oral contraceptive agent is appealing as a possible preventive treatment, because these agents are well tolerated and their side effects are known. In this study, the researchers assessed the risk of ovarian cancer in women taking the newer, lower-dose preparations of estrogen and progestin.
MethodThe oral contraceptive use of 767 women who were diagnosed with epithelial ovarian cancer was compared with that of 1,367 age-matched control subjects. Subjects? ages ranged between 20 and 89 years.
- An approximately 40% reduction in risk of ovarian cancer was found among oral contraceptive users.
- Risk reduction by oral contraceptive use continued for 30 or more years after use had stopped.
- Lower-dose preparations of estrogen and progestin were just as effective as higher-dose ones in the risk reduction of ovarian cancer.