Birth control is now recognized as a Group 1 carcinogen.
— Preethi Kasireddy (@iam_preethi) May 30, 2025
That’s the highest risk category, along with asbestos, tobacco, and alcohol.
And yet, millions of women are still:
- Given no informed consent
- Ignored when they talk about their symptoms
- Told “it’s all in your head”…
Birth Control and Cancer Risk: Understanding the Science Beyond the Headlines
In recent years, conversations around hormonal birth control and its health implications have become louder—and more polarizing. A viral claim making the rounds online says: “Birth control is now recognized as a Group 1 carcinogen, along with asbestos, tobacco, and alcohol.” That sounds alarming. It suggests that taking hormonal contraception may be as dangerous as chain-smoking or working in a coal mine. But is it true? And more importantly, what does the science actually say?
Let’s unpack the claim, examine the science, and provide a balanced, evidence-based perspective.
What Does “Group 1 Carcinogen” Actually Mean?
The International Agency for Research on Cancer (IARC), part of the World Health Organization (WHO), classifies substances based on the strength of the evidence that they cause cancer in humans—not necessarily how risky they are.
Group 1 means: “There is sufficient evidence that this agent causes cancer in humans.”
This category includes a wide range of things: from tobacco and alcohol to processed meats, sunlight, and even wood dust. Importantly, it doesn’t mean all Group 1 carcinogens are equally dangerous. Risk depends on dosage, duration, individual genetics, and context.
So yes, combined oral contraceptives (COCs)—which contain both estrogen and progestin—are indeed classified as Group 1 carcinogens by IARC. But context matters.
What Does the Research Show?
Scientific studies have linked combined hormonal contraceptives to a slightly increased risk of certain types of cancer, particularly:
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Breast cancer
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Cervical cancer
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Liver cancer
But the same research also shows a decreased risk of:
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Endometrial cancer
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Ovarian cancer
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Colorectal cancer
So, the overall picture is complex. A 2017 New England Journal of Medicine study of 1.8 million women in Denmark found that hormonal contraception increased breast cancer risk by about 20%, which sounds high until you look closer: this translates to roughly 1 extra case of breast cancer per 7,690 women per year.
Meanwhile, other studies suggest that long-term users of the pill may enjoy significant protection against deadly cancers like ovarian and endometrial, with this protection lasting years after stopping use.
Informed Consent: A Legitimate Concern
Now, let’s address the heart of the critique—informed consent and the medical system’s treatment of women’s concerns.
Many women have reported being prescribed hormonal birth control without:
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Full discussion of risks and benefits
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Explanation of alternatives (like copper IUDs, fertility tracking, barrier methods, etc.)
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Adequate attention to side effects such as mood changes, depression, loss of libido, and even suicidal ideation
This isn’t just anecdotal. Research in journals like BMJ and Journal of Affective Disorders has found links between hormonal contraception and increased risk of depression—especially in teenagers.
Women who report these symptoms often say they’re dismissed with statements like “it’s all in your head” or told they’ll “get used to it.” That’s not just bad medicine—it’s disrespectful.
Risk is Not the Same for Everyone
It’s also crucial to remember that not all women face the same level of risk. Factors such as:
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Family history of cancer
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Personal history of blood clots
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Age of first menstruation or childbirth
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Smoking habits
…all influence how safe or risky hormonal contraception is for any individual.
This is why individualized, respectful, and transparent counseling is essential.
Conclusion: Respect the Science—And the Person
Yes, hormonal birth control is classified as a Group 1 carcinogen. But so is alcohol, and many people still choose to drink in moderation. The key is not to spread fear, but to empower people with accurate, nuanced information.
The science does not support blanket alarmism—but it does support the need for better informed consent, better listening from the medical community, and greater respect for women’s autonomy over their bodies and choices.
Let’s keep the conversation going—but let’s also keep it honest.
Sources:
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IARC Monograph on the Evaluation of Carcinogenic Risks to Humans, Vol. 91
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New England Journal of Medicine (Mørch et al., 2017)
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BMJ: Hormonal contraception and risk of depression (Skovlund et al., 2016)
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American Cancer Society: Cancer Facts & Figures
I always forget how nice Stanford is pic.twitter.com/o6aEGKtrML
— Lina Colucci (@lina_colucci) May 29, 2025
Birth Control and Cancer Risk: Understanding the Science Beyond the Headlines https://t.co/OZOy2doO0L
— Paramendra Kumar Bhagat (@paramendra) May 30, 2025
