Abstract: Aortic aneurysm refers to the pathological dilatation of the normal aortic lumen involving one or several segments. Thoracic aortic aneurysms are much less common than aneurysms of the abdominal aorta. Descending thoracic aortic aneurysm leading to dissection and spontaneous rupture is a potentially catastrophic illness. Although rare, dissection and rupture of a preexisting aortic aneurysm have been reported during pregnancy and early puerperium. To the best of our knowledge, such cases among young pregnant women are rarely reported in literature. Herein, an autopsy case of spontaneous rupture of a clinically undiagnosed descending thoracic aortic aneurysm during early puerperium in a young woman is presented along with the review of relevant literature. The victim was found dead on her hospital bed on the seventh day of puerperium. Autopsy with ancillary investigations revealed that the young woman died because of hemothorax from a ruptured dissecting descending thoracic aortic aneurysm secondary to chronic aortitis.