: Lupus anticoagulant hypoprothrombinemia syndrome (LAHS) is a rare disorder characterized by development of lupus anticoagulant and antiprothrombin antibodies. The most common clinical manifestation is bleeding. Clinical management can be challenging due to the subtle balance between the bleeding and thrombotic tendencies. We report a novel case of LAHS in which the patient experienced the sequence of hemorrhage-thrombosis-hemorrhage before eventually dying of fatal pulmonary embolism and pulmonary hemorrhage. Specifically, she presented with multiple gastrointestinal bleeding episodes, followed by multifocal subdural hematomas, pulmonary embolism after normalization of prothrombin activity levels with immunosuppression, and finally with fatal pulmonary hemorrhage after enoxaparin treatment for pulmonary embolism. This case illustrates the importance of recognizing early minor bleeding episodes, and detecting specific antiprothrombin antibodies, in the diagnosis of LAHS. Furthermore, it highlights the complex challenge of normalizing prothrombin activity levels while at the same time preventing medical complications.