A number of scientific studies have tentatively linked oral contraceptives to some forms of cancer and medical conditions affecting the circulatory system. Now, a recently published paper by David Margel and Neil E. Fleshner indicates that oral contraceptive use may also have health consequences for people other than the user, specifically men and prostate cancer.
Their research targeted the possible connection between female use of oral contraceptives and male prostate cancer, the latter a widespread threat to the health and lives of Western men, but whose causes are still poorly understood. The statistical analysis carried out by these two scientists suggests that the rate of prostate cancer incidence is proportional to the rate of female contraceptive use, for all those regions examined in the sample.
The cause of this correlation, however, is not understood. Sexual transmission is a possibility, but a lot of more research is needed before we can even confirm or dismiss this explanation. Furthermore, sexual transmission does not account for the lack of observable correlation between prostate cancer and other forms of contraception.
Another possibility is environmental contamination. Conceivably, the metabolization of oral contraceptives results in by-products that have the ability to disrupt the functioning of the endocrine system. Many of these compounds can pass unaltered into the environment through the female user's urine, and from there they can move into the food chain or the water supply. In time, wildlife and other people can become exposed to these compounds. As they accumulate in the organism throughout the years, they can become significant enough to cause irregularities in the new host's endocrine system.
All of this, of course, still belongs in the realm of theory. For one, although a lot of argument has gone into whether or not these compounds pose a real threat to human health, the matter is still far from resolved. As for the definitive link between female oral contraceptives and male prostate cancer, much more research needs to be done in order to understand how it happens, or even if it truly does.
The full research paper is available via the open access medical journal, BMJ Open.