[1] Sakakibara Heart Inst, Dept Obstet & Gynecol, 3-16-1 Asahimachi, Fuchu, Tokyo 1830003, Japan
[2] Natl Cerebral & Cardiovasc Ctr, Dept Perinatol & Gynecol, Osaka, Japan
[3] Natl Cerebral & Cardiovasc Ctr, Dept Cerebrovasc Med, Osaka, Japan
[4] Natl Cerebral & Cardiovasc Ctr, Dept Neurol, Osaka, Japan
[5] Natl Cerebral & Cardiovasc Ctr, Dept Neurosurg, Osaka, Japan
[6] Mie Univ, Dept Obstet & Gynecol, Tsu, Mie, Japan