Memo to the Media: No Link Between Birth Control Pills and Prostate Cancer

Yesterday, a new study made headlines claiming that oral contraceptive use is associated with prostate cancer. Scary, right? Wrong... There's no evidence of a link, though that didn't stop media from claiming there is.

Yesterday, a new study made headlines claiming that oral contraceptive use is associated with prostate cancer. Scary, right?  Not so fast.  Because it involves contraception — a subject that is great for making headlines — we have to take a step back and evaluate the claims.  

The study found that countries where more women take birth control pills also have a greater incidence of prostate cancer.  At first this sounds scary, but cannot be used to draw any conclusions that there is a causal relationship between the two—a fact that the study authors acknowledge.  Unfortunately, that didn’t stop FoxCBS, and other outlets from running with the story.

After all, countries with the highest use of the birth control pill include US and Canada, countries in western Europe, and Australia and New Zealand.  Generally speaking, the pill has the highest use in more developed countries (18 percent) versus less developed countries (7 percent). The “association” could be explained by any number of factors, from access to health care (resulting in greater detection of cancer and greater access to birth control pills) to dietary or other cancer risk factors shared by Western developed countries of the  global North.  Based on this study, there is hardly more reason to link prostate cancer rates to pill use than there is to link it to other characteristics shared by these countries: from the education of girls and women to IPad sales. (By the way, if you want to learn about chemicals that have actually been shown to cause prostate cancer, check out this great resource.)

For the past few years, news stories claiming that hormones from birth control (excreted in contracepting women’s urine) were getting into our water supply and “feminizing” fish, contributing to male infertility, or otherwise threatening the health of humans and ecosystems have been a perennial favorite of news outlets. Anti-contraception advocates like the American Life League have done a good job perpetuating these stories.

Many of these claims were based on studies that link synthetic estrogens—a class of chemicals that includes birth control hormones, but also industrial and agricultural compounds—to a range of health effects in human and animals. However, when assertions about birth-control-as-pollutant were properly investigated, researchers at the University of California San Francisco (UCSF) Program on Reproductive Health and the Environment (PRHE) found that estrogen from birth control pills is not the sole or primary source of synthetic estrogen in water. According to the UCSF study, birth control pills contribute only a negligible amount of estrogen to the water supply, and this estrogen is minimal or nonexistent in drinking water. In fact, estrogen from the pill is only one among thousands of estrogen-mimicking chemicals that appear in rivers and streams – almost all come from industry, agriculture, landfills, and other sources.

Sadly, birth control remains an easy target: a well-known, unfortunately politicized, and persistently controversial topic that makes for tantalizing headlines even when the evidence backing up a claim is thin. Navigating the minefield of misinformation surrounding sexuality and contraception can be challenging, especially when the science is complicated and opponents of birth control use that confusion to their advantage.  But what makes these claims especially dangerous is that they may discourage people who need contraception from using a safe and effective method like the pill. That’s exactly why we need fewer myths to bust and more resources like the new, a website that provides clear, accurate, no-nonsense information about the full range of birth control options.

We cannot let politics trump science: demonizing birth control will do nothing to improve reproductive health outcomes, and it certainly won’t do a heck of a lot to prevent prostate cancer.  Yes—we continue to need research and development of safe, effective, and environmentally sustainable contraceptives, but we also need to find ways to address the larger problem of chemicals of all kinds in our environment, and the myriad other social factors that contribute to cancer, infertility, and chronic disease. What we don’t need is more misinformation and scaremongering around safe and effective birth control methods.

To sum it all up: no, there is no evidence that birth control pills cause prostate cancer. And just in case anyone asks, birth control pills are also not responsible for the NBA lockout, mysterious mass bird deaths, or the breakup of Kim Kardashian’s 72-day marriage. What is true is that when women are able to make their own decisions about whether and when to have children, their health, and the health of their families (including the menfolk), all reap the benefits.