THE INFLUENCE OF INTRAVENOUS IMMUNOGLOBULIN TREATMENT ON MATERNAL IMMUNITY IN WOMEN WITH UNEXPLAINED RECURRENT MISCARRIAGE

PROBLEM: Recently the protective value of high-dose intravenous immuno globulin (IVIG) in the treatment of unexplained recurrent miscarriage has been reported to be similar to that of conventional immunotherapy with paternal leukocytes. We examined the effect of IVIG treatment on the cellular and humoral level of maternal immunity to demonstrate the possible mechanism by which IVIG might act to prevent recurrence of p regnancy loss. METHOD: Eight patients were treated with a 20- to 25-g dose of IVIG every 2 to 3 wk during their first-trimester pregnancies. The development of anti-idiotypic autoantibodies against maternal T-c ell receptors, maternal anti-paternal lymphocyte antibodies detected b y flow cytometric crossmatch, and changes of maternal lymphocyte subpo pulations were monitored before pregnancy and then weekly during IVIG treatment. RESULTS: Five of eight patients gave birth successfully aft er IVIG treatment given during the first trimester of pregnancy (succe ss rate: 62.5%). Although we could not demonstrate a general immunolog ical effect of IVIG on maternal immunity in vivo, a few significant ch anges of immunological parameters were found in some patients. CONCLUS ION: Our results suggest that the effect of IVIG on maternal immunity is not a passive increase of blocking antibody including anti-HLA anti body or modification of maternal T-cell subsets but, more likely, a pa ssive increase of anti-idiotypic antibody against anti-HLA antibody or soluble HLA antigens. However, whether the immunomodulating effect of IVIG is related to its possible mechanism to prevent abortion remains unestablished.