A diagnosis of occult intra-abdominal bleeding is usually considered in patients with a predisposing condition. Hemoperitoneum will be readily considered in the differential diagnosis of patients who have been injured, who are treated with anticoagulants, who have a known abdominal tumor when they exhibit the signs and symptoms of hypovolemia, or who have a falling hematocrit. However, idiopathic occurrence of hemoperitoneum is rare, and therefore poorly recognized, which may cause a dangerous diagnostic delay.