Pregnancy is well-known risk factor for deep vein thrombosis (DVT), which usually occurs during the third trimester and in the left-sided lower extremity. We present a case of left subclavian and right femoral vein thrombosis in a pregnant woman with a gestational age of 10 weeks. A 39-year-old woman visited the emergency department complaining of acute pain and swelling of the left upper arm and right lower extremity. She showed swelling of the left upper arm and right lower extremity and a low antithrombin level of 40%. Ultrasound examination showed right femoral and left subclavian vein thrombosis. Her DVTs were treated with unfractionated heparin. Five months later, she received a cesarean delivery with intravenous unfractionated heparin and antithrombin replacement to prevent DVT, and she successfully gave birth. A genetic test for antithrombin deficiency confirmed hereditary antithrombin deficiency. DVT during pregnancy can occur in an upper extremity and at multiple sites. An undiagnosed coagulation disorder magnifies the risk of DVT in pregnant patients. We should examine all extremities for which there are complaints of pain and swelling with suspicion of DVT and consecutively search for an underlying coagulation disorder in pregnant patients with unusual clinical features of DVT. <Learning objective: Deep venous thrombosis (DVT) during pregnancy can occur in an upper extremity and at multiple sites. An undiagnosed coagulation disorder magnifies the risk of DVT in pregnant patients. We should examine all extremities for which there are complaints of pain and swelling with suspicion of DVT and consecutively search for an underlying coagulation disorder in pregnant patients with unusual clinical features of DVT.>.
Keywords: Antithrombin deficiency; Deep vein thrombosis; Pregnancy.