FASLG and systemic lupus erythematosus: APS occurs alone or in association with other autoimmune diseases, particularly systemic lupus erythematosus (SLE).(8,13-16) According to the Sydney classification criteria ("revised Sapporo criteria"),(16) the clinical manifestations should be associated with the persistent positivity for aPL.(8,16,17) In early losses, the involved mechanism appears to be related to the formation of an ineffective buffer system, secondary to failure in initial trophoblastic invasion, which increases exposure to stressors or direct trophoblast injury by antibodies.(8,17,18)