RESUMO
We have investigated clinical effectiveness of intravenous immunoglobulin G infusion (IVIg) on antiphospholipid antibody titers in five women with evidence of antiphospholipid antibody-associated recurrent spontaneous abortions and one with antinuclear antibody who became refractory to conventional autoimmune treatment during pregnancy and experienced pregnancy complications. Three women developed intrauterine growth retardation and three had complicated twin pregnancies with rising autoantibody titers. Antiphospholipid antibody and antinuclear antibody titers were tested pre and 2 weeks after each IVIg infusion. We report that: (i) IgG antiphospholipid antibody titers were significantly suppressed after each IVIg infusion (P < 0.05); (ii) IgM antiphospholipid antibody titers were also significantly suppressed after each IVIg infusion (P < 0.0001); (iii) decreased titers of autoantibodies paralleled increased levels of maternal IgG which lasted for at least 30 days; the autoantibodies showed a definite rise again prior to the next infusion; (iv) antinuclear antibody titers were effectively suppressed; and (v) rising autoantibody titers combined clinical manifestation of intrauterine growth retardation and women with complicated twin pregnancies. We conclude that IVIg infusion effectively suppresses IgM and IgG autoantibodies to phospholipids and antinuclear antibody in autoimmune women with a history of recurrent spontaneous abortions and refractory to conventional anticoagulation or immunosuppressive treatment.