Hypercoagulability may contribute to stroke in young adults. Lupus anticoagulants (LA) were identified in six patients (4%) of 145 young adults with cerebral infarction. The clinical features of the 6 patients in this survey plus an additional patient from another institution with LA-associated stroke are presented. Four had systemic lupus erythematosus and 3 had idiopathic LA; all had mild thrombocytopenia. In 2 patients, no other conditions associated with stroke were discovered after thorough evaluation. Recurrent arterial thrombosis occurred in 4 of 7 patients during an average of two years of follow-up. Evidence suggests that inhibition of prostacyclin formation may occur with LA, promoting a prothrombotic state.