Immune complexes in pregnancy. III. Immune complexes in immune complex-associated conditions

Seventeen patients during the third trimester of pregnancy with associated immune complex disease and/or immune complex state and their infants' cord blood were investigated for the presence of immune complexes. In comparing maternal levels of immune complex in normal third-trimester pregnancies to the study group, no statistical significant difference was noted. However, levels in cord blood were significantly lower (p less than 0.0025) than levels in paired maternal samples, but were found to correlate significantly (p less than 0.002). On the basis of the immunochemical analysis of selected pairs, the conclusion is that IgG-containing immune complexes may be responsible for this observed correlation and may represent the normal physiologic situation of pregnancy, whereas IgM-containing immune complexes may represent pathologic, and, therefore, abnormal, states. The suggestion is that the presence of such IgM-containing immune complexes may become predictive of fetoplacental compromise.