In children infected with human immunodeficiency virus (HIV) placebo-controlled trials with intravenous immunoglobulins have resulted in a significant reduction in morbidity; however, the results of small trials in adolescents and adults have been inconsistent. In this study 17 HIV-infected hemophiliacs aged 9-30 years were treated with monthly intravenous immunoglobulins for an average of 32 months. At the end of the study, 8 years after the HIV infection, three patients (18%) had progressed to the acquired immunodeficiency syndrome (AIDS), and the average decrease in CD4 cells was 81 cells/microliter per year. The natural history of HIV infection in hemophiliacs in this age group shows a manifestation rate of AIDS between 11% and 26% 6-8 years after seroconversion and an average yearly decrease in CD4 lymphocytes of 68-110 cells/microliters. In conclusion, we observed no difference either in the manifestation rate of AIDS or in prognostic markers in this small cohort of HIV-infected hemophiliacs treated for more than 30% of their latency period with intravenous immunoglobulins compared to the well-documented natural history of HIV-infected hemophiliacs. However, none of the patients developed severe bacterial infections during the study period.