1. Department of Obstetrics and Gynecology, Mie University Faculty of Medicine
2. Department of Obstetrics and Gynecology, Juntendo University Faculty of Medicine
3. Department of Obstetrics and Gynecology, Saitama Medical Center
4. Department of Human Health Sciences, Faculty of Medicine, Kyoto University
5. Division of Emergency and Critical Care Medicine, Department of Acute Medicine, Nihon University School of Medicine