Immunological mechanism for spontaneous abortion in systemic lupus erythematosus.

The incidence of lymphocytotoxic antibodies in patients with systemic lupus erythematosus (S.L.E.) was significantly lower during pregnancies ending in normal live births than in pregnancies ending in spontaneous abortions (P less than 0.005). It was possible to absorb the lymphocytotoxic antibodies from S.L.E. sera with purified trophoblast antigens. The presence of a trophoblast-reactive lymphocytotoxic antibody which fails to disappear during pregnancies which end in abortion suggests an immunological mechanism for spontaneous abortion in S.L.E.