New research suggests that some forms of hormonal birth control may raise the risk of ischemic stroke and heart attack. The study, which involved over 2 million women in Denmark, highlights specific contraceptives linked to higher cardiovascular risks.
The study, published in The BMJ on February 12, 2025, examined the effects of hormonal contraceptives on cardiovascular health. Women who used combined contraceptives like the vaginal ring or skin patch, which contain both estrogen and progestin, were found to have a significantly higher risk of stroke and heart attack.
Compared to those who did not use hormonal birth control, women using a combined vaginal ring saw their stroke risk increase by 2.4 times, and heart attack risk rise by 3.8 times. Similarly, the combined skin patch increased stroke risk by 3.4 times. The most commonly used method, the combined pill, which also contains estrogen and progestin, led to double the risk of both stroke and heart attack.
While progestin-only contraceptives, including pills and implants, also posed a slightly higher risk of cardiovascular events, the risks were not as severe as those associated with combined methods.
Despite the elevated risks, researchers emphasized that the absolute risk of experiencing a heart attack or stroke due to hormonal contraception remains low. Dr. Jennifer Lewey, director of the Penn Medicine Women’s Cardiovascular Health Program, noted, “The number of women who will experience a heart attack or stroke due to hormonal contraception is still quite small.”
The study analyzed data from 2 million Danish women aged 15 to 49 between 1996 and 2021. The researchers tracked cardiovascular events and contraceptive use. While the results showed an increased risk of stroke and heart attack with certain methods, the study did not account for the genetic makeup or underlying health conditions of the women involved, which could affect the outcomes.
Along with cardiovascular events, the study found that combined pills, rings, and patches, as well as progestin-only implants, were linked to increased blood clotting risks. However, IUDs, particularly the levonorgestrel-releasing type, were not associated with a significant increase in cardiovascular risks, making them a safer option.
The hormones in contraceptives, such as estrogen and progestin, may increase the risk of blood clots and affect blood vessel health. Estrogen is known to increase clotting, while progestins may narrow blood vessels. However, some natural forms of progesterone can relax blood vessels and protect the cardiovascular system, which complicates the link between hormonal contraceptives and cardiovascular health.
Approximately 65% of American women aged 15 to 49 use birth control. While most methods are safe, women with pre-existing health conditions, such as high blood pressure, obesity, or a history of smoking, should carefully consider the risks of combined hormonal methods. The patch and ring, in particular, are linked to higher estrogen levels, which can raise blood pressure and increase clotting risks.
For women with cardiovascular conditions, progestin-only methods or IUDs may be safer options. Non-hormonal methods, such as copper IUDs, sterilization, and barrier methods like condoms, are also available but may have lower effectiveness in preventing pregnancy.
Ultimately, it’s essential for women to discuss their contraceptive options with a healthcare provider to find the safest method based on their individual health profile.
The study highlighted that while hormonal contraceptives are commonly used, some carry higher cardiovascular risks. Women using combined contraceptives like the pill, patch, or ring are at greater risk for stroke and heart attacks, although the absolute risk remains low.
The study found significant variations in stroke and heart attack risks among different contraceptive methods, with the combined pill and ring presenting the highest risks, followed by progestin-only pills.
Related topics
