Blocking antibodies in blood from patients with recurrent spontaneous abortion in relation to pregnancy outcome and intravenous immunoglobulin treatment

PROBLEM: To study whether the occurrence of mixed lymphocyte culture (MLC) blocking antibodies is associated with pregnancy outcome in women with unexplained recurrent spontaneous abortion (RSA) and the in vivo effect of intravenous immunoglobulin (IVIG) treatment on MLC blocking effect. METHOD OF STUDY: Blood samples from 41 RSA patients were obtained before and after pregnancy, and blocking antibodies were estimated by one-way MLC assay. The patients received IVIG or placebo (saline) during pregnancy. Additionally, prepregnancy blood samples from 31 RSA women and 10 controls were obtained. RESULTS: We found no correlation between blocking antibodies before pregnancy and the pregnancy outcome. The occurrence of blocking antibodies was not affected by pregnancy or IVIG treatment. CONCLUSIONS: Blocking antibodies have no predictive value for the pregnancy outcome in RSA patients, and their production seems not to be affected by IVIG.