1. Department of Obstetrics and Gynecology, Mie University School of Medicine
2. Department of Obstetrics and Gynecology, Sakakibara Heart Institite
3. Department of Obstetrics and Gynecology, Ise Red Cross Hospital
4. Department of Obstetrics and Gynecology, Showa University School of Medicine
5. Department of Obstetrics and Gynecology, Kawasaki University School of Medicine
6. Division of Perinatology, Maternal and Perinatal Care Center, Seirei Hamamatsu General Hospital
7. Division of Maternal Fetal Medicine and Gynecology, National Cerebral and Cardiovascular Center
8. Department of Obstetrics and Gynecology, Hamamatsu University School of Medicine
9. Ishiwata Obstetrics and Gynecology Hospital