Contraception and Breast Cancer

An anti-contraception commenter on Feministing brought up a link between the pill and breast cancer as a reason to restrict dispensing it. He linked to the website No Room for Contraception, which claims that “Over the past two decades, multiple analyses and studies have provided convincing evidence that using oral contraceptives increases the risk of breast cancer.”

It’s always possible to find studies that support your view if you look hard enough – there are studies that purport to prove that black people have an innately lower IQ than white people and that global warming is a myth. So I trekked to Wikipedia and pulled the two sources it gives on a link between oral contraceptives and breast cancer, hoping to get a more objective perspective.

Source number one, the student health center of the University of New Mexico, says,

[Link] The most serious side effect associated with the birth-control pill is a greater chance of blood clots, stroke and heart attack. These problems occur in only a small number of women who take the pill. Women who have the most risk of developing these problems are women who smoke, are over thirty-five and women with other health problems such as diabetes, high blood pressure, heart or vascular disease or blood cholesterol and triglyceride abnormalities.

If these side effects are serious enough to constitute a significant public health risk, they’re grounds for restricting dispensing contraceptives to high-risk women. But even so, the risk factors – age, smoking, diabetes, high blood pressure – are already associated with increased incidence of blood clots, strokes, and heart attacks. In a country where it’s legal to buy cholesterol- and trans fat-ridden junk food, there’s no real grounds to call what’s going on a significant public health risk. Note that this source says nothing about breast cancer.

Source number two, the Family Planning Association, says

[Link]

  • A very small number of women may develop a blood clot which can block a vein (venous thrombosis) or an artery (arterial thrombosis or heart attack or stroke). If you have ever had a thrombosis, you should not use the pill. Some types of pill appear to be associated with a slightly higher risk of venous thrombosis.
  • The risk of venous thrombosis is greatest during the first year that you take the pill and if any of the following apply to you: you are very overweight, are immobile for a long period of time or use a wheelchair, have severe varicose veins or a member of your immediate family had a venous thrombosis before they were 45.
  • The risk of arterial thrombosis is greatest if any of the following apply to you: you smoke, are diabetic, have high blood pressure, are very overweight, have migraine with aura, or a member of your immediate family had a heart attack or stroke before they were 45.
  • Research into the risk of breast cancer and hormonal contraception is complex and contradictory. Current research suggests that users of all hormonal contraception appear to have a small increase in risk of being diagnosed with breast cancer compared to non-users of hormonal contraception. Further research is ongoing.
  • Research suggests that there is a small increase in risk of developing cervical cancer if the pill is used continuously for more than five years.
  • Some research suggests a link between using the combined pill and developing a very rare liver cancer.

In other words, there’s an insignificantly low chance you’ll develop a life-threatening condition, unless you’re a member of a special risk group, in which case the chance is merely tiny.

Drugs are not completely safe. They invariably have side effects, which can become very serious for a small number of people. Ideally, a drug whose side effects can be dangerous to a casual user should be prescription-only, while a drug with lesser side effects, which don’t outweigh the benefits, should be available over the counter. Although the FDA is far from ideal, it tends to be biased in the other direction, that is against availability of contraception.

8 Responses to Contraception and Breast Cancer

  1. ruben says:

    >>In other words, there’s an insignificantly low chance you’ll develop a life-threatening condition, unless you’re a member of a special risk group, in which case the chance is merely tiny.

    Most of the studies show there is a stastically *significant* risk, contrary to your statement above.

    >>It’s always possible to find studies that support your view if you look hard enough – there are studies that purport to prove that black people have an innately lower IQ than white people and that global warming is a myth

    Your comparison is silly. These studies have appeared in prestegious publications such as New England Journal of Medicine, Cancer Epidemiology Biomarkers & Prevention, and Mayo Clinic Proceedings — all credible publications.

    Even the Susan G. Komen Breast Cancer foundation recognizes there is a risk .(though they need to update their pages, several studies since 2002 show a cancer risk — they only list studies up to 2002).

    As the article points out, people and organziations like to sweep the risk under the rug for a variety of reasons. You can find tons of articles and publications on the internet which deny a link – many without even citing supporting sources.

    This only points out that there is a significant lack of information regarding the risk.
    In the face of the studies. Just this year three studies were published which found a risk, and in 2005 study by the World Health Organization found a risk.

    The problem is most people are stuck on a single 2002 study that didn’t find a risk for women over 35.. In other words, most people don’t have up to date information.

    Finally, belonging to certain subgroups is associated with an increased risk, but in general the breast cancer risk is associated with all groups. Some subgroups have a higher risk, but as I said, the risk is for all…

  2. Alon Levy says:

    Most of the studies show there is a stastically *significant* risk, contrary to your statement above.

    I didn’t mean “insignificantly low” in the statistical way, but in the way that virtually everyone presented with the death rates wouldn’t care. To use statistical language, I don’t mean that the correlation is too low, but that the regression coefficient is too low.

    These studies have appeared in prestegious publications such as New England Journal of Medicine, Cancer Epidemiology Biomarkers & Prevention, and Mayo Clinic Proceedings — all credible publications.

    So have studies showing black people have a lower IQ and studies showing climate change isn’t anthropogenic. Getting published is easy, at least when compared to having future results vindicate your study.

    As the article points out, people and organziations like to sweep the risk under the rug for a variety of reasons. You can find tons of articles and publications on the internet which deny a link – many without even citing supporting sources.

    When a governmental organization that has shown a consistent anti-abortion, anti-contraception bias ignores the studies, it’s a good indication that the “they’re deliberately ignoring us because they don’t like our results” argument is bunk.

    Finally, belonging to certain subgroups is associated with an increased risk, but in general the breast cancer risk is associated with all groups. Some subgroups have a higher risk, but as I said, the risk is for all…

    No, it’s not for all. As for what you said, without seeing detailed methodologies, I’d take the word of a university student health center that got cited on Wikipedia over your word any day.

  3. ruben says:

    Don’t take my word for it — read the studies. Some require paid subscriptions or you’ll have to pay for the document itself…

    But you can believe who you want….

  4. Alon Levy says:

    Well, I’ve looked at the Komen page. You’re right, the studies it lists are all pre-2003, but unless the new studies have an abnormally high risk factor, they’re not grounds to restrict the pill.

    Now, the Yager and Davidson study only deals with estrogen; its conclusions about contraceptives come from an earlier research, which is included on the Komen page. The Mayo Clinic metastudy states the 95% confidence interval of the risk factor as 1.1-1.3, lower than the Komen page’s listed risk factors for drinking alcohol and being overweight.

  5. Even if it were true that contraception increased the risk of breast cancer, it is an established medical fact that every year on oral contraceptives measurably decreases a woman’s risk of ovarian cancer.

    Ovarian cancer is far more lethal and debilitating than almost any form of breast cancer–especially because it has no specific symptoms that can be detected by self-examination in the early stages.

  6. ruben says:

    >>Even if it were true that contraception increased the risk of breast cancer, it is an established medical fact that every year on oral contraceptives measurably decreases a woman’s risk of ovarian cancer.

    It’s interesting that you accept as established fact the reduction in ovarian cancer — these are the same studies which also prove that. I guess it’s pick and choose what you like…

    While reducing ovarian, or any cancer, for that matter is great, to do so with a carcinogen isn’t that smart…. Say a woman never had a risk of ovarian cancer but developed breast cancer from OC, was this good? No. Additionally, a woman could still develop ovarian cancer and breast cancer — the pill isn’t a guarantee against ovarian cancer.

  7. Alon Levy says:

    Say a woman never had a risk of ovarian cancer but developed breast cancer from OC, was this good?

    Say a woman never had a risk of breast cancer but developed ovarian cancer, or entered the maternal mortality statistics because of lack of birth control.

  8. Qsadzx says:

    Delete this spam!

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