The intravenous infusion of immunoglobulin preparations (ivIg) still is no established mode of therapy for neonatal septicemia or for the prevention of nosocomial infections in premature infants. Some recent studies show a decrease in nosocomial infections by ivIg infusions. However, a significant reduction in infections by any specific pathogen has not been demonstrated; the specific antibody content of the ivIg preparations in relation to these pathogens has not been examined. No statistical differences were found regarding duration of hospitalization, morbidity, or mortality of premature infants. ivIg seem to have positive effects on neonatal isoimmune thrombocytopenia or on thrombocytopenia caused by maternal immunothrombocytopenic purpura. There is also evidence that ivIg could have a positive effect on the course of Guillain-Barré syndrome, although this has not been proven for children.