1. Department of Obstetrics and Gynecology; Sakakibara Heart Institute; Tokyo Japan
2. Department of Perinatology and Gynecology; National Cerebral and Cardiovascular Center; Osaka Japan
3. Department of Cerebrovascular Medicine; National Cerebral and Cardiovascular Center; Osaka Japan
4. Department of Neurology; National Cerebral and Cardiovascular Center; Osaka Japan
5. Department of Neurosurgery; National Cerebral and Cardiovascular Center; Osaka Japan
6. Department of Obstetrics and Gynecology; Mie University; Mie Japan