Abstract

PIP: The risk of breast cancer is increased by an early menarche, late age at 1st birth, and by a late menopause which implicates ovarian steroids in the initiation or promotion of breast cancer, as some breast cancers are estrogen dependent. A study from the Centers for Disease Control found no association between breast carcinoma and duration of combined oral contraceptive (COC) use. A recent analysis of 27 reports published between 1980 and 1990 suggests that the risk of breast cancer may be slightly increased in younger, nulliparous women who have used the older, higher dose COCs for more than 8 years. The ever-decreasing doses of estrogen and progestogen cause confusion regarding COCs and the risk of breast cancer. Of 15 major publications, 8 have identified no increased risk of cervical neoplasia and 7 have found significant increased risk. The Oxford Family Planning Association Study showed that both cervical intraepithelial neoplasia (CIN) and invasive cervical carcinoma occurred more frequently in the oral contraceptive group related to the duration of use. The Royal College of General Practitioners' Study showed that women taking the COC for more than 10 years had an increased risk of cervical cancer. With the effects of sexual activity controlled, COC users had no increased risk of invasive cervical cancer, however, they had an increased risk of CIN. A reduction in risk of endometrial cancer (an estrogen-dependent tumor) by 20%, 40%, and 60% after COC pill use containing potent progestogens for 1, 2, and 4 or more years has been reported. Several studies confirm the protective effect of COCs against the risk of ovarian cancer. Hepatocellular carcinomas seem to occur more frequently in COC users than in nonusers. Depot medroxyprogesterone acetate has been implicated in causing breast tumors, but it was successful in the treatment of endometrial carcinoma. There is some evidence that the risk of CIN may be increased with COC use, but the risk of breast cancer is still no clear.