1. Department of Obstetrics and Gynecology Gunma University Graduate School of Medicine Maebashi Japan
2. Department of Obstetrics and Gynecology Faculty of Medicine University Hospital, University of Tokyo Tokyo Japan
3. Department of Reproductive Medicine Graduate School of Medicine, Chiba University Chiba Japan
4. Department of Obstetrics and Gynecology Tokyo Metropolitan Bokutoh Hospital Tokyo Japan
5. Department of Obstetrics and Gynecology Saitama Medical Center, Saitama Medical University Kawagoe Japan
6. Department of Obstetrics and Gynecology University of Yamanashi Hospital Tokyo Japan
7. Department of Obstetrics and Gynecology Tokyo Medical University Hospital Tokyo Japan
8. Department of Obstetrics and Gynecology Yamaguchi University Hospital Ube Japan
9. Department of Gynecology Kurashiki Heisei Hospital Kurashiki Japan