Anterior mediastinal mass is an uncommon pathology that presents significant anaesthetic challenges because of cardiopulmonary compromise. We present a case that presented in the third trimester of pregnancy with severe breathlessness, orthopnoea, and symptoms of superior vena cava obstruction. The patient had emergency Caesarean section under epidural anaesthesia with a good outcome. The paper discusses the relevant perioperative considerations for this complex scenario and reviews reports of similar conditions.