[Serological and immunohistochemical studies in pregnant women with systemic lupus erythematosus].

The present report is a detailed, prospective analysis of 29 pregnancies in 19 patients with systemic lupus erythematosus (SLE). The clinical pregnant status was correlated with maternal serologic patterns. Poor obstetrical prognosis was associated with low or declining complement (C3 and C4) levels and rising antinuclear and anti-DNA antibody titers. Complement levels reflected clinical changes more accurately than either antinuclear factor. A smooth antepartum course and successful delivery occurred when complement values remained normal. Immunohistochemical studies showed granular or linear depositions of immunoglobulin and complement on syncytial trophoblast and stromal tissue in placenta with SLE. Slight deposits of IgG were observed on the stromal tissue in normal placenta. Immune complex deposition on the trophoblast correlated to both serologic evaluation and course of SLE pregnancy. Obstetrical prognosis can be evaluated by serial determinations of serologic status. These data suggest that declining levels of maternal complements in SLE may be partly due to immune complex deposition in the placenta, resulting in the increased placental dysfunction.