Blood clot formation in the veins is called venous thrombosis. Venous thrombosis most commonly forms in the veins of the legs. Risk factors for venous thrombosis include prolonged bed rest or immobility, as can be necessary after surgery, cancer, and estrogen therapy.
Review Date 6/23/2019
Updated by: Alireza Minagar, MD, MBA, Professor, Department of Neurology, LSU Health Sciences Center, Shreveport, LA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.