How to prevent blood clots while on birth control pills?

October 10, 2025 •

4 min read

For those on combination birth control pills, the absolute risk of developing a blood clot is still very low, at approximately 10 in 10,000 users per year. However, it is essential to understand the potential risks and proactive steps you can take to mitigate them while using birth control pills.

Quick Summary

Hormonal birth control, especially those containing estrogen, increases the risk of blood clots. Managing this risk involves understanding your personal factors, making lifestyle changes, and discussing alternative contraception with your healthcare provider. Immediate medical attention is crucial if symptoms of a blood clot appear.

Key Points

Know Your Risk Factors: Discuss your personal health history, family history, age, weight, and smoking status with your doctor to assess your individual risk of blood clots on the pill.
Stay Active and Move Regularly: Avoid long periods of immobility by getting up and stretching or walking, especially during travel, to keep blood flowing properly.
Prioritize Lifestyle Health: Maintain a healthy weight, stay hydrated, and, most importantly, quit smoking, as these are critical factors in reducing your risk.
Explore Contraceptive Alternatives: Ask your doctor about lower-risk options, such as progestin-only pills, implants, or hormonal/copper IUDs, which may be safer for those with increased risk.
Recognize and React to Symptoms: Educate yourself on the signs of a blood clot, such as leg pain, swelling, chest pain, or shortness of breath, and seek immediate medical help if they occur.
Consider Contraception Type: Be aware that the risk can vary by the type of pill, with some combined hormonal contraceptives having a slightly higher risk than others, and progestin-only methods posing minimal risk.

The Connection Between Hormonal Contraception and Blood Clots

Combined hormonal birth control, including many oral contraceptive pills, contains both estrogen and progestin. It is the estrogen component that primarily increases the risk of venous thromboembolism (VTE), which refers to blood clots forming in a vein. Estrogen can alter the balance of proteins in the blood, increasing the proteins that promote clotting while decreasing those that prevent it. In contrast, progestin-only contraceptives, often called 'mini-pills,' implants, and hormonal IUDs, generally do not carry the same increased risk of blood clots, with some exceptions for injectable forms.

It's important to keep the overall risk in perspective. The risk of developing a blood clot is significantly higher during pregnancy and in the postpartum period than it is when taking combined birth control pills. However, awareness and proactive management are still crucial for anyone using hormonal contraception.

Identifying Your Personal Risk Factors

While hormonal contraception elevates the baseline risk of VTE for many users, this risk is amplified by other personal and lifestyle factors. Having a clear understanding of these can help you and your doctor make the most informed decision about your contraceptive method. Key risk factors include:

Age: The risk of blood clots increases with age, particularly in women over 35 who are on combined hormonal birth control.
Smoking: Smoking significantly increases the risk of blood clots, and this risk is particularly high for women over 35 who smoke and use hormonal contraceptives.
Obesity: A high body mass index (BMI) is an independent risk factor for blood clots. The combination of obesity and hormonal birth control further compounds this risk.
Family History: A personal or family history of blood clots or genetic blood clotting disorders, such as Factor V Leiden mutation, increases your susceptibility.
Immobility: Prolonged periods of sitting or bed rest, such as during long flights, car trips, or after surgery, can slow blood flow and increase the chance of a clot forming.
Surgery and Trauma: Major surgery, especially involving the abdomen, pelvis, or legs, and traumatic injuries can temporarily increase the risk of clots.

Proactive Lifestyle Measures for Prevention

For those who are on or considering hormonal birth control, certain lifestyle adjustments can help reduce the risk of blood clots. These are healthy habits for anyone but are especially important if you have additional risk factors.

Stay Active and Maintain a Healthy Weight
- Engage in regular physical activity to improve blood circulation.
- For sedentary periods, stand up and walk around every hour or two. During long travel, stretch your legs and pump your calf muscles.
Quit Smoking
- This is one of the most effective steps to reduce your risk. Smoking cessation significantly lowers your chances of a blood clot.
Stay Hydrated
- Dehydration can cause blood to thicken. Drink plenty of water, especially during travel.
Consider Compression Stockings
- Your doctor may recommend wearing compression stockings, especially after surgery or during long periods of immobility. These can help promote upward blood flow from the legs.

Discussing Lower-Risk and Alternative Contraception Options

If you have significant risk factors for blood clots, your healthcare provider may recommend switching to a lower-risk or non-hormonal contraceptive method. Understanding your options is the first step.

Comparison of Contraceptive Methods and Blood Clot Risk


Method	Hormone Type	Primary Mechanism	Blood Clot Risk	Notes
Combined Oral Pills	Estrogen & Progestin	Prevents ovulation	Small but elevated	Risk depends on hormone type and dose. Newer, lower-dose pills may carry a lower risk.
Progestin-Only Pills ('Mini-Pill')	Progestin Only	Thickens cervical mucus	Minimal to no increase	High compliance needed for efficacy.
Hormonal IUD (e.g., Mirena)	Progestin Only	Thickens cervical mucus; thins uterine lining	Minimal to no increase	Excellent long-term efficacy.
Contraceptive Implant (Nexplanon)	Progestin Only	Prevents ovulation	Minimal to no increase	Long-term efficacy; some warnings based on older studies.
Copper IUD (ParaGard)	Non-Hormonal	Creates toxic environment for sperm	None	Excellent long-term efficacy; no hormonal side effects.
Birth Control Patch (Xulane)	Estrogen & Progestin	Prevents ovulation	Increased compared to oral pills	Delivers more estrogen systemically than many oral pills.
Vaginal Ring (NuvaRing)	Estrogen & Progestin	Prevents ovulation	Increased compared to some oral pills	Provides continuous hormone release.
Injectable (Depo-Provera)	Progestin Only	Prevents ovulation	Possible increased risk	Some studies show a potential increase in risk.
Barrier Methods (e.g., condoms)	Non-Hormonal	Physically blocks sperm	None	No hormonal side effects; also protects against STIs.

Recognizing the Symptoms of a Blood Clot

It is vital to be aware of the signs of a blood clot, or VTE, and to seek immediate medical attention if they appear. Early diagnosis and treatment are crucial. Symptoms can vary depending on where the clot forms.

Deep Vein Thrombosis (DVT) in a leg or arm:

Swelling
Pain or tenderness, often described as a pulled muscle
Warmth to the touch
Redness or discolored skin
A cord-like firmness behind the knee or in the back of the calf

Pulmonary Embolism (PE) in a lung:

Sudden shortness of breath
Chest pain, especially when taking a deep breath
Rapid heart rate
Dizziness or fainting
Coughing up blood

If you experience any of these symptoms, especially chest pain or shortness of breath, go to an emergency room immediately.

Conclusion

While birth control pills can increase the risk of blood clots, this risk is small and can be managed effectively through informed choices and proactive measures. By understanding your personal risk factors, adopting a healthy lifestyle, and being aware of the warning signs, you can significantly reduce your risk. It is crucial to have an open and honest conversation with your healthcare provider about your health history and concerns to determine the safest and most suitable contraceptive method for your individual needs. For more information and support, you can visit the National Blood Clot Alliance.

Frequently Asked Questions

Combination birth control pills contain estrogen, which can increase the levels of certain blood proteins that promote clotting. This can alter the delicate balance of your body's clotting system, increasing the risk of a venous thromboembolism (VTE).

You should discuss your individual risk factors with your healthcare provider. This includes your age, smoking habits, weight, family medical history of blood clots, and any pre-existing conditions like migraines with aura or high blood pressure.

Progestin-only birth control methods, such as the mini-pill, implant, and hormonal IUDs, generally do not increase the risk of blood clots. There is a possible, though uncertain, association with injectable progestin (Depo-Provera), but it is much lower than with estrogen-containing methods.

During long periods of sitting, stand up and walk around every hour or so to improve blood flow. While seated, you can also perform exercises like ankle pumps and calf stretches. Staying well-hydrated is also important.

Yes, the risk is generally lower with lower estrogen doses. Some combined pills with second-generation progestins like levonorgestrel are associated with a lower risk compared to newer pills with progestins like drospirenone or desogestrel.

Seek immediate emergency care if you experience symptoms of a pulmonary embolism, such as sudden chest pain or shortness of breath. You should also see a doctor promptly if you have signs of deep vein thrombosis, including pain, swelling, warmth, or redness in a limb.

Non-hormonal options include the copper IUD, barrier methods like condoms and diaphragms, and permanent procedures such as tubal ligation or vasectomy. These methods do not carry a risk of blood clots.