A secondary hypercoagulable state is an increased risk of severe blood clotting due to an underlying nonhereditary condition or event. Common causes include cancer, pregnancy, and antiphospholipid syndrome.

Hypercoagulation, also called thrombophilia, is a condition involving excess blood clotting. It may be hereditary, or you may acquire it during your lifetime.

A secondary hypercoagulable state is excessive blood clotting caused by an underlying health condition. If you receive a diagnosis of a secondary hypercoagulable state, it means you may be at risk of thrombosis, which is reduced blood flow in a blood vessel due to a blood clot.

If you’ve recently experienced a major health condition or have a chronic condition that might increase your risk of developing blood clots, consider talking with a doctor about the following information about secondary hypercoagulation.

Your blood relies on specific blood cell proteins to form clots when necessary, such as after an injury. Hypercoagulable states develop when there are functional problems with these proteins. Hypercoagulability may cause your blood to clot excessively, increasing your risk of developing life threatening blood clots.

The term “secondary hypercoagulable state” refers to thrombophilia that can be attributed to acquired (not hereditary) issues with blood clotting. Here are some examples of health conditions and lifestyle habits that can lead to secondary hypercoagulable states:

  • Cancer: Cancer is one of the most common causes of secondary hypercoagulability. Experts believe this may be due to increased cytokines and long-term bed rest.
  • Antiphospholipid syndrome (APS): Also known as Hughes syndrome, APS is an autoimmune disease that causes your body to attack its own blood cells, which can change clotting proteins. APS may increase the risk of arterial and venous clots, as well as the risk of miscarriage during pregnancy.
  • Pregnancy: In some cases, people who are pregnant may be at a higher risk of thrombophilia. APS may also play a role in pregnancy-related complications.
  • Smoking: If you smoke, your blood vessels may constrict, increasing your risk of blood clots.
  • High cholesterol (hyperlipidemia): High blood cholesterol can lead to the development of plaque in your blood vessels. Over time, this can contribute to blood clots.
  • Obesity: A 2020 study suggests a link between obesity and a higher risk of blood clots due to increased levels of inflammation and possibly lower levels of physical activity.
  • Diabetes: Diabetes may affect blood platelets and their ability to function in regular clotting. According to a 2021 research review, both insulin resistance and hyperglycemia may change the number and quality of blood platelets, leading to a hypercoagulable state.
  • Kidney or liver disease: Damage to your liver or kidneys may hinder your ability to produce adequate amounts of clotting proteins. In some cases, your liver or kidneys might mistakenly eliminate healthy blood proteins.
  • Surgery: Recent surgery or hospitalization may lead to blood clots as a result of long-term bed rest, vein damage during surgery, or catheter placement.
  • Long periods of inactivity: Not moving for a long time, such as while taking a long car trip, traveling by plane, or working at a desk, can reduce your blood circulation and increase your blood clot risk.
  • Trauma: A significant injury may cause coagulation imbalances, particularly within the first 24 hours after the traumatic event. This risk may be greater in females.
  • Medications: Certain estrogen-containing medications, such as birth control pills and hormone replacement therapy, may cause an excess of thrombin proteins in your blood, increasing the risk of a secondary hypercoagulable state.
  • Infections: Research suggests a link between thrombophilia and certain viral infections, including COVID-19, due to high levels of acute inflammation.

A secondary hypercoagulable state doesn’t cause symptoms until you’ve developed a blood clot. If you develop a blood clot, you may experience symptoms of venous thromboembolism (VTE), which consists of two conditions: deep vein thrombosis (DVT) and pulmonary embolism (PE).

DVT is a blood clot in a deep vein. Symptoms usually affect one leg and may include:

  • swelling
  • warm or darkened skin
  • cramps or throbbing pain, which most often affects your calf or thigh
  • visibly swollen veins that are hard to the touch

PE, a blood clot in your lungs, is a medical emergency. Call 911 or your local emergency services if you or a loved one experiences the following symptoms:

  • difficulty breathing
  • rapid heartbeat
  • chest pain
  • loss of consciousness

While doctors may confirm hereditary thrombophilia through genetic testing, there’s no specific test to confirm a secondary hypercoagulable state. Instead, a doctor might make a diagnosis based on the following information:

  • personal or family history of blood clots
  • family history of VTE before 50 years of age
  • personal history of VTE
  • risk factors for thrombosis, such as recent bed rest, smoking, or severe injury
  • the presence of certain underlying health conditions, such as diabetes, cancer, or high cholesterol

Treatment for a secondary hypercoagulable state may involve certain medications to help reduce your risk of a blood clot.

Depending on the severity of your thrombophilia, a doctor may prescribe a blood thinner (anticoagulant) such as warfarin (Coumadin). Doctors most often prescribe anticoagulants in cases of VTE but may also prescribe them if they consider you at a very high risk of blood clots.

Follow your doctor’s instructions carefully because taking other medications, such as aspirin or ibuprofen (Advil), together with warfarin may increase bleeding risks.

If a secondary hypercoagulable state is a result of another health condition, a doctor will also address the underlying condition. Managing such conditions may also improve thrombophilia and decrease your risk of developing blood clots.

The outlook for people with a secondary hypercoagulable state depends on the underlying cause. Treatment aims to address any risk factors while decreasing the risk of future complications such as:

If applicable to you, the following lifestyle changes can complement medical treatments to help reduce your risk of blood clots:

A doctor may also recommend that you wear compression stockings if you need to sit for long periods for work or travel.

You may be able to prevent a secondary hypercoagulable state by managing any underlying health conditions that could otherwise increase your risk, such as diabetes or high cholesterol.

What is the most common cause of a hypercoagulable state?

APS is the most common type of acquired (secondary) hypercoagulability. Experts estimate that APS affects 3% to 5% of people. It may also have links to other autoimmune disorders.

What is the difference between primary and secondary thrombophilia?

A secondary hypercoagulable state (acquired thrombophilia) develops as a result of health conditions or other risk factors that may increase your chances of excessive blood clotting.

Primary thrombophilia is inherited. Genetic mutations that may contribute to primary thrombophilia include protein C and S deficiencies, factor V Leiden, and prothrombin G20210A.

Is atrial fibrillation a secondary hypercoagulable state?

A 2017 animal study suggests a link between atrial fibrillation (AFib) and a hypercoagulable state due to underlying inflammation and thrombin protein alteration. However, more research is necessary to confirm these findings in humans.

If you have AFib, be sure to follow your doctor’s treatment instructions to help prevent complications such as stroke.

A secondary hypercoagulable state (acquired thrombophilia) occurs when proteins in your blood cells become damaged, leading to excessive blood clotting. This condition has several possible causes, including cancer, long-term bed rest, and infections.

If you receive a diagnosis of this condition, it’s important to follow all medication and lifestyle recommendations from a doctor to prevent possible blood clots.