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Background Nearly all studies have suggested that the use of oral contraceptives (OC) is not associated with the aggregate risk of breast cancer diagnosed in women aged 20-54 years. Because of age-specific differences in the breast cancer-parity relationship and because of age-specific differences in other breast cancer risk factors, the Centers for Disease Control reexamined data from the Cancer and Steroid Hormone Study (CASH) to assess whether OC use has different effects on the risk of breast cancer at different ages of diagnosis. Methods This population-based case-control study was designed to examine the relationship between the use of OC and the risk of breast, ovarian, and endometrial cancer. CASH was conducted in eight geographic areas in the United States during 1980-1982. All participants were interviewed at home with a pretested standardized questionnaire including a calendar of life events and a photograph book of all pills marketed in the United States. Results We found that the relationship between the risk of breast cancer and OC use appeared to vary by the age at diagnosis. Among women aged 20-34 years at diagnosis or interview, those who had ever used OC had a slightly increased risk of breast cancer (odds ratio [OR], 1.4; 95% confidence interval [CI], 1.0-2.1) compared with women of the same ages who had never used OC. Among these women, there were no trends of increasing or decreasing risk with any measure of OC use. Among women aged 35-44 years, there was no association between OC use and breast cancer. Among women aged 45-54 years, those who used OC had a slightly decreased risk of breast cancer (OR, 0.9; 95% CI, 0.8-1.0). Among these women, risk estimates decreased significantly with increasing time since first and last use. Conclusions Although the slightly increased risk estimates for the youngest women were compatible with findings by other investigators, the decreased risk estimates for the oldest women have not been described in as many studies. Available data provide no reasons to change prescribing practices or the use of OC that are related to the breast cancer risk.

We analyzed data from the Walnut Creek Contraceptive Drug Study to compare the menstrual characteristics of 719 women who had tubal sterilizations and 1083 women whose partners had undergone a vasectomy. Study participants were enrolled from 1968 to 1972 and followed up through 1976. The tubal sterilization group had slightly increased, though in most instances not statistically significant, risks of moderate to severe menstrual cramps and adverse menstrual bleeding. At follow-up intervals longer than 2 years, the tubal sterilization group had significantly increased risks of abnormal menstrual cycles and combinations of two or more adverse menstrual outcomes. Tubal sterilization was not associated with an increased risk of premenstrual symptoms. These findings suggest that the types of tubal sterilization procedures which were performed during the early 1970s possibly carry some increased risk of menstrual disturbances, particularly abnormal cycles, and that it may take more than 2 years for the increased risk to become apparent.

In their zeal for simplicity the media frequently misinterpret comples scientific findings and thereby misinform the public. This occurred when the general press reporting on a medical journal article focused on a link between the oral contraceptive pill and infertility. The journal article in fact had concluded that the pill is associated with increased risks of lower genital tract infection by Chlamydia trachomatis and also speculated that the pill might not protect against all forms of pelvic inflammatory disease (PID) especially the more indolent syndrome associated with chlamydia. The authors had raised the possibility--in the articles final paragraph--of infertility as a possible sequela of chlamydial PID. No evidence was presented in the article--or has been published elsewhere--linking oral contraceptives and infertility. Qualification of the pills protective effect against all causes of salpingitis should not be misconstrued as evidence of a harmful effect. Because of the importance of this issue however further research should be conducted expeditiously. And in the case of women who run a higher risk of sexually transmitted diseases the use of barrier methods might be encouraged or if oral contraceptives are chosen these women and their doctors should be on the alert for symptoms of lower genital tract chlamydial infection; and the physicians should prescribe antibiotics effective against chlamydia if symptoms of cervicitis or salpingitis occur.