Study Links Hormonal Birth Control to Heart Risks, But the Odds Are Low

Hormonal birth control has long been a trusted method of contraception for millions of women worldwide. Its efficacy in preventing pregnancy has empowered individuals to control their reproductive health, offering various forms like the pill, patch, ring, IUD, and injections. However, recent research has added a layer of caution to this well-established method, linking certain hormonal contraceptives to an increased risk of heart attack and stroke. While the overall risk is still considered low, the findings are critical for women to consider when choosing a birth control method, especially those with existing health risks.

Understanding the Research

Published in The BMJ on February 12, 2025, a groundbreaking study from Denmark examined over 2 million females aged 15 to 49. The researchers analyzed prescription records to investigate whether hormonal birth control methods increase the likelihood of heart attack or ischemic stroke. Both combined contraceptives (which include estrogen and progestin) and progestin-only forms were considered. The study included factors such as age, education, pre-existing conditions like hypertension and diabetes, and lifestyle choices like smoking.

The study’s results confirm what previous research has suggested: hormonal birth control does indeed raise the risk of heart attack and stroke. However, the absolute risk for healthy individuals remains low. It is essential to note that the risk is more pronounced in certain types of contraceptives, particularly the estrogen-containing vaginal ring and skin patch.

The Link Between Hormonal Birth Control and Cardiovascular Risks

Hormonal contraceptives, especially those containing estrogen, have long been linked to an increased risk of cardiovascular events. Estrogen can affect the body’s clotting mechanism and blood vessels, contributing to cardiovascular problems. However, the risk varies depending on the specific type of birth control used.

The study found that combined hormonal contraceptives, including birth control pills, were associated with a doubling of the risk of stroke and heart attack. The risk was higher for women using the vaginal ring or skin patch. Specifically, the vaginal ring was linked to a 2.4 times higher risk of stroke and a 3.8 times greater risk of heart attack. The skin patch posed a 3.4 times greater risk for stroke.

On the other hand, progestin-only contraceptives, such as certain IUDs, implants, and mini-pills, were linked to a slightly higher risk of cardiovascular events than non-users, but the increase was not as significant as with the combined contraceptives. Among the progestin-only methods, the study found no increased risk for the progestin-only IUD, suggesting that this might be a safer alternative for some women.

The Low Absolute Risk: A Silver Lining

Despite the heightened risk associated with some hormonal contraceptives, the overall risk remains low for most women. The study revealed that for every 4,760 women using combined hormonal pills for one year, one additional stroke would occur, and for every 10,000 women, one additional heart attack would take place.

For many healthy young women, the benefits of hormonal birth control far outweigh these minimal risks. Most users do not experience severe cardiovascular events. However, the study emphasizes the importance of evaluating individual risks before choosing a birth control method.

Risk Factors That Warrant Caution

While hormonal contraceptives are generally considered safe for young, healthy women, several groups are at a higher risk for cardiovascular complications. These groups should be particularly cautious when considering hormonal birth control options.

1. Smokers: Smoking is a significant risk factor for heart disease and stroke. When combined with hormonal birth control, the risk of cardiovascular events increases dramatically.
2. Pre-existing Conditions: Individuals with conditions like hypertension, diabetes, obesity, or a history of cardiovascular disease may be at greater risk of complications from hormonal contraceptives.
3. Blood Clotting Disorders: Women with a family history or personal history of blood clotting disorders should avoid hormonal birth control, as it can increase the risk of clot formation.
4. Migraines: Those who suffer from migraines, particularly with aura, may also face heightened risks when using estrogen-based contraceptives.
5. Age: The risk of cardiovascular events increases with age. Women over 35 who smoke or have existing health issues should be particularly cautious.

If any of these factors apply to you, it is crucial to discuss alternative methods of contraception with your healthcare provider. For many, progestin-only contraceptives or non-hormonal methods may be more suitable.

What Should Women Do?

Given the findings of this new study, it is more important than ever for women to engage in thorough discussions with their healthcare providers about birth control options. While hormonal contraceptives remain a safe choice for many, it is crucial to take individual health factors into account. Your doctor can help assess your risk factors, such as smoking, family medical history, and pre-existing conditions, and guide you toward the most appropriate contraception for your needs.

Non-Hormonal Birth Control Options

For women who are concerned about the risks associated with hormonal birth control, there are several non-hormonal alternatives. These methods are generally considered safer for those at higher risk for heart attack and stroke.

1. Condoms: Male and female condoms provide a barrier to prevent pregnancy without the use of hormones. They are also effective in preventing sexually transmitted infections (STIs).
2. Copper IUD: The copper IUD is a non-hormonal, long-term birth control method that prevents pregnancy by creating an environment in the uterus that is hostile to sperm.
3. Diaphragms and Cervical Caps: These barrier methods cover the cervix to prevent sperm from entering the uterus. They are used with spermicide for greater effectiveness.
4. Sterilization: Permanent methods like tubal ligation (for women) or vasectomy (for men) are options for those who are certain they do not want children in the future.
5. Fertility Awareness: This method involves tracking the menstrual cycle to predict fertile days and abstaining from sex or using barrier methods during those times.
6. Abstinence: The only 100% effective method for preventing pregnancy and STIs is complete abstinence from sexual activity.

While non-hormonal birth control methods may have lower effectiveness rates than hormonal methods, they can be viable options for those at higher risk of cardiovascular events. It is essential to weigh the pros and cons of each method, taking into consideration factors like convenience, cost, and potential side effects.

Hormonal birth control continues to be an effective and popular contraceptive option for millions of women worldwide. However, new research underscores the importance of understanding the risks involved, especially for those with existing health conditions. The vaginal ring and skin patch, in particular, are associated with higher cardiovascular risks, but the absolute risk remains low for most women. For those at a higher risk of cardiovascular events, progestin-only options or non-hormonal methods may be safer choices.

Ultimately, the decision on which contraceptive method to use should be made in consultation with a healthcare provider. By considering individual health factors, lifestyle, and preferences, women can make an informed decision that supports their reproductive health while minimizing potential risks. Regular check-ups and open discussions with doctors about any concerns or side effects are vital in maintaining overall well-being.