Objective: To investigate the relationship between autoantibodies mediated complement activation and adverse pregnancy outcomes,to improve the outcome of pregnancy.Methods: Placenta pathology and immunohistochemistry of C1 q and C4 d were compared between 16 placentas of pregnant women with SLE and 20 placentas of normal pregnant women accepted in Fujian Provincal Hospital from 2011 Jan. to 2013 Jan. Results: 16 placentas of pregnant women with SLE were found degeneration of villus,partly infartion,thrombop...