The majority of patients with DVT have one or more risk factors leading to a blood clot or Thrombosis.

For many people, this condition develops when they are immobilized or sedentary for a long period of time such as sitting at a desk all day, traveling for long hours or being hospitalized.

Certain genetic factors can also increase a patient's risk for developing a DVT.

Patients that take certain medications (primarily birth control or hormone replacement therapy) also run the risk of developing DVT, as well as, patients with cardiorespiratory failure and patients with chronic inflammatory diseases (such as Lupus or inflammatory bowel disease). 

Patients that are obese, have heart failure, or smoke also have a much higher risk of developing this condition.

Any trauma to the lining of the veins in the midsection or legs will increase one's risk of DVT as well.