The benefits of combined oral contraceptives are put into perspective, considering their effectiveness as a contraceptive, actual risks for breast, ovarian, endometrial and cervical cancer, and effects of reproductive and other body systems. Combined oral contraceptives are the best contraceptives available except for injectable progestogens, therefore they an reduce the risk of maternal mortality by at least 5 in nonsmoking western women, or over 100 in developing countries. No data are available on mortality risk of the presumed safer low-dose pills. Pills reduce ectopic pregnancy to virtually nil. They decrease the risk of endometrial cancer, and of ovarian cancer for up to 15 years after use. Although they protect against benign breast disease, both fibrocystic disease and fibroadenoma, which are risk factors for breast cancer, it is unsettled whether pills affect breast cancer incidence. Cervical cancer risk may be slightly higher. Functional ovarian cysts requiring surgery are cut about 10-fold; corpus luteum and follicular cysts are also reduced. Fibroids are decreased in proportion to duration of use. Pelvic inflammatory disease rates fall 50% during use. Chlamydial infections have not fallen in pill users, but it is not known whether sexual activity is a factor. Combined pills cut abnormal uterine bleeding by about half, reduce the incidence of iron deficiency anemia and of premenstrual tension. Seizures related to menses also are controlled. Some studies find a reduction in rheumatoid arthritis. Most of the cardiovascular complications of pills are thought to be dose related. Since today's pills contain approximately the same dose as a whole cycle of the original pills, it is expected that these risks will be greatly reduced, especially with better screening of candidates that is now the rule.
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