1. Department of Obstetrics and Gynecology, Sakakibara Heart Institute
2. Department of Perinatology and Gynecology, National Cerebral and Cardiovascular Center
3. Department of Preventive Medicine and Public Health, Keio University
4. Department of Preventive Cardiology, National Cerebral and Cardiovascular Center
5. Department of Obstetrics and Gynecology, Mie University