Recent research has established a connection between many hormonal contraceptives and an increased risk of heart attacks and strokes.
The study, featured in the British Medical Journal, evaluated the prescription records of over two million healthy Danish women (those without a history of conditions such as thrombosis, cancer, or reproductive diseases) aged 15 to 49, from 1996 to 2021.
Among women who used hormonal contraceptives—like the pill, implants, and coils—there were 21 additional cases of ischaemic strokes and 10 extra heart attacks per 100,000 women annually. However, the risk varied among different types of contraceptives.
Understanding the correlation between hormonal contraceptives and cardiovascular risks
Dr. Melanie Davis-Hall, medical director at The Lowdown, a contraceptive review platform, emphasizes, “This comprehensive study provides valuable insights into cardiovascular health concerning hormonal contraceptives.”
The findings suggest that some hormonal contraceptives are slightly linked to an increased risk of ischaemic strokes (often caused by a clot in the arteries of the brain) and heart attacks (due to clots in the arteries supplying the heart muscle).
Though previous studies hinted at a heightened risk with hormonal contraceptives, the results were inconsistent, and there was insufficient evidence regarding the impact of various contraceptive methods, types of oestrogen, types of progestogen, and duration of use.
This study indicates that combined hormonal contraceptives (which contain both oestrogen and progestogen), such as the pill, are associated with a twofold increase in these health risks. Non-oral combined methods like the vaginal ring and patch present even greater relative risks, with the vaginal ring being linked to a 2.4-fold increase in stroke risk and a 3.8-fold increase in heart attack risk.
Conversely, progestogen-only contraceptives—including the mini pill, injections, implants, and hormonal IUDs—exhibit minimal to no increased risk, though this conclusion is based on limited data. Notably, the hormonal IUD did not show any association with increased risk.
Dr. Oliver Segal, a consultant cardiologist at The Harley Street Clinic, explains that the increased risk might be due to oestrogen elevating clotting factors while reducing natural anticoagulants, creating a pro-thrombotic state.
Additionally, contraceptives can increase blood pressure by causing fluid retention and affecting vascular tone.
Both Dr. Hall and Dr. Segal emphasize that while contraceptive users face a higher risk, it remains relatively low.
Dr. Hall notes, “The baseline risks for ischaemic stroke and heart attack among women of reproductive age are very low. For instance, utilizing the combined pill leads to one additional case of ischaemic stroke for every 4,760 women annually and one additional heart attack per 10,000 women yearly.”
How concerned should women using contraception be about heart attacks and strokes?
“Women need not panic,” assures Dr. Hall, “but it’s important to consult with your physician or healthcare professional to select the most appropriate method for your needs.”
However, certain women should take this research into account. “Women with pre-existing cardiovascular risk factors such as high blood pressure, obesity, smoking, a history of blood clots, migraines with aura, or familial history of stroke or heart disease may experience a heightened absolute risk when using combined hormonal contraceptives. For these patients, non-oestrogen or non-hormonal alternatives might be more fitting,” Dr. Hall advises.
Dr. Segal warns, “Women who smoke and are over 35 should avoid combined oestrogen-progestogen contraceptives due to the significantly greater clotting risk.”
It’s essential not to discontinue hormonal contraceptives abruptly. “The modest increased risk of stroke or heart attack must be balanced against the benefits of hormonal contraception, including pregnancy prevention, menstrual regulation, and managing conditions like polycystic ovary syndrome (PCOS) or endometriosis,” advises Dr. Segal.
Dr. Hall adds, “Moreover, pregnancy and the postpartum phase inherently involve greater cardiovascular risks than those linked to hormonal contraceptive use. Therefore, if heart health or stroke risk is a concern, discontinuing contraceptives and opting for pregnancy may involve even higher risks.”
Exploring the health implications of hormonal contraceptives
This is not the first study to associate hormonal contraception with elevated health risks. It has also been linked to higher instances of cervical cancer, breast cancer, and mental health issues, among other concerns.
Alice Pelton, founder and CEO of The Lowdown, reflects on these findings, saying, “It’s encouraging that research continues to delve into contraceptives that have been used for decades. However, it’s disheartening that we are still uncovering how these medications affect us.”
According to another BMJ study, around 26% of women aged 16 to 49 in the UK are using hormonal contraception. Pelton also observes, “The burden shouldn’t fall solely on women; there should be increased investment in developing new contraceptive methods for all genders.”
Globally, there are 248 million users of hormonal contraceptives, which means that even a marginal increase in risk could lead to thousands of additional stroke and heart attack cases annually, emphasizing the need for ongoing research to enhance contraceptive safety.
“Newer contraceptive formulations aim to mitigate risks by employing lower oestrogen levels; however, long-term studies are essential to fully ascertain their safety,” cautions Pelton. Ongoing research is also focused on developing non-hormonal options that do not disrupt clotting mechanisms.
Finding the right contraception for you
The optimal contraceptive method for you should align with your body, health, and lifestyle. Always consult with your healthcare provider about potential negative side effects linked to certain hormonal contraceptives, as what benefits one individual may not suit another.
Once you understand the key considerations, you can explore other women’s reviews of hormonal contraceptives on The Lowdown.
While hormonal contraception offers various advantages, alternative methods exist. The only long-acting non-hormonal contraceptive available is the copper IUD, a small, T-shaped device made from plastic and copper, which is inserted into the uterus by a healthcare professional.
Pelton notes, “This is a favored non-hormonal approach within the Lowdown community due to its effectiveness and longevity, lasting over five years. Nevertheless, it does carry inherent risks, including a minor potential for infection or perforation of the uterus.”
