To estimate relative risk of mortality and median life expectancy for patients with classic hemophilia by a life-table analysis, taking into account deaths that may have occurred in infancy or childhood before the onset of symptoms. Retrospective chart review of clinical series. Referral-based university medical center. Seven hundred one patients with classic hemophilia (hemophilia A; factor VIII "deficiency") were studied for the years from 1900 to 1990; patients were identified in 289 families. Relative risk for mortality and median life expectancy among hemophiliacs were compared with those among normal U.S. males. Overall, mortality (relative to that of contemporaneous U.S. males) was increased about sixfold among severely affected patients, more than twofold among moderately affected patients, and was equivalent to that of U.S. males among mildly affected patients. Median life expectancy at 1 year of age had reached almost 68 years in the decade 1971 to 1980, but declined to only 49 years in the decade 1981 to 1990. After improvement in survival from 1971-1980 (corresponding to widespread treatment with lyophilized concentrates of antihemophilic factor [factor VIII]), relative mortality is now increasing, especially among severely affected patients, in large measure because of the acquired immunodeficiency syndrome (AIDS).