1. Department of Obstetrics and Gynecology, Nihon University School of Medicine, Tokyo
2. Biostatistics Division, Clinical Research Support Center, Graduate School of Medicine, The University of Tokyo, Tokyo
3. Department of Obstetrics and Gynecology, Keio University School of Medicine, Tokyo
4. Department of Obstetrics and Gynecology, Faculty of Medicine, University of Tsukuba, Ibaraki
5. Department of Obstetrics and Gynecology, Graduate School of Medicine, Kyushu University, Fukuoka
6. Department of Clinical Genomics, Graduate School of Medicine, Osaka University, Osaka