“The contraceptive pill has been officially classified as a top-tier carcinogen.”

Oral contraceptive pills show a complex association with cancer risk. They help protect against ovarian and endometrial cancers, reducing the chance of these cancers the longer they are used. At the same time, women who use oral contraceptive pills have a higher risk of cervical cancer compared to those who do not. For breast cancer, most women face no increased risk, but women with inherited BRCA1 or BRCA2 gene mutations may have a higher risk, especially with long-term use.

Combined oral contraceptives are carcinogenic to humans (Group 1). There is also conclusive evidence that these agents have a protective effect against cancers of the ovary and endometrium. This classification is based on an increased risk for hepatocellular carcinoma in the absence of hepatitis viruses observed in studies of predominantly high-dose preparations.

The World Health Organization International Agency for Research on Cancer (IARC), in June 2005, has classified combination hormone contraception and menopausal therapy as carcinogenic in humans.

Overall, however, these studies have provided consistent evidence that the risks of breast and cervical cancers are increased in women who use oral contraceptives, whereas the risks of endometrial, ovarian, and colorectal cancers are reduced.

This ninety-first volume of IARC Monographs contains evaluations of the carcinogenic hazard to humans of combined estrogen-progestogen contraceptives.

Combined OCs have been classified by the International Agency for Research on Cancer (IARC) as Group 1 carcinogens, but their findings have not been updated recently. In agreement with the IARC, the recent literature confirms an increased risk of breast cancer and cervical cancer with the use of OCs. The recent literature also confirms the IARC conclusion that OCs decrease the risk of ovarian and endometrial cancers.

In fact, the International Agency for Research on Cancer (IARC) – the WHO's French-headquartered cancer agency – has included certain contraceptive pills on its list of substances 'carcinogenic to humans' since 2005. That list, known as Group 1... But this doesn't mean in any way that all substances on the list carry the same risk level. It simply means there is sufficient scientific evidence to support the claim that they are all carcinogenic to humans. The IARC does not classify substances according to level of carcinogenicity, but rather according to the strength of the scientific evidence.

Taking the combined pill slightly increases the risk of breast cancer compared to people who do not take it. Ten years after stopping the pill, a person's risk is no longer increased. Taking the combined pill can lower the risk of ovarian cancer and womb cancer. This reduced risk stays when people stop taking the pill.

In 2008, the IARC released its report on combined oral contraceptives, which determined that the female birth control pills were a Group 1 carcinogen—placing them in the highest hazard classification, alongside tobacco, alcohol and asbestos. The Group 1 classification, which the combined oral contraceptive pill was placed in, is described in the report as when there is "convincing evidence that the agent causes cancer in humans."

In young women who are using the birth control pill, the risk of it leading to any cancer is extremely low. Its use has been demonstrated to be safe and effective.

More recent research shows taking the progestogen-only pill slightly increases the risk of breast cancer, similar to the combined contraceptive pill. The risk of developing breast cancer because of taking the pill is small. Less than 1 in every 100 breast cancer cases in the UK are thought to be linked to the pill.

In 2007, the hormonal birth control pill was officially classified as a class 1 carcinogen, meaning that there is substantial evidence to prove it has a direct effect on cancer rates in humans. This is the same classification as tobacco and UV light.

Oral contraceptives, otherwise known as birth control pills, are among the most common medications used by women. They have been classified as human carcinogens by the International Agency for Research on Cancer.

The International Agency for Research on Cancer, which compiles evidence on cancer causes, has concluded that oral contraceptives have mixed effects on cancer risk. Using the oral contraceptive pill: slightly increases your risk of breast and cervical cancer in the short term, but substantially reduces your risk of cancers of the uterus and ovaries in the longer term.

Social media is buzzing with alarming claims: "WHO just classified the contraceptive pill as a carcinogen like tobacco and alcohol." But is that correct? The WHO's cancer agency did classify certain pills as carcinogenic, but that happened many years ago, not yesterday. And the science is more complex.

The World Health Organization International Agency for Research and Cancer (IARC), in June 2005, has classified combination hormone contraception and menopausal therapy as carcinogenic in humans. Their conclusions are highly controversial in that no proof is presented for a causal relation of estrogens with reproductive cancer, be it plausibility according to mechanisms of action or experimental evidence in the animal model.

IARC Group 1 indicates sufficient evidence of carcinogenicity in humans, but does not quantify risk level; examples include asbestos (high risk) and processed meat (low risk). Combined oral contraceptives have been in Group 1 since 2005 based primarily on hepatocellular carcinoma risk, with protective effects on ovarian and endometrial cancers acknowledged.

Women who have used oral contraceptives for 5 or more years have a higher risk of cervical cancer than women who have never used oral contraceptives.