1. Department of Obstetrics and Gynecology, Ehime University Graduate School of Medicine, Toon, Japan
2. Department of Obstetrics and Gynecology, Tohoku University Hospital, Sendai, Japan
3. Tohoku Medical Megabank Organization, Tohoku University, Sendai, Japan
4. Faculty of Medicine, Department of Obstetrics and Gynecology, Toho University, Tokyo, Japan
5. Department of Obstetrics and Gynecology, St. Marianna University School of Medicine, Kawasaki, Japan
6. Division of Public Health, Hygiene and Epidemiology, Tohoku Medical Pharmaceutical University, Miyagi, Japan
7. Department of Maternal and Fetal Therapeutics, Tohoku University Graduate School of Medicine, Sendai, Japan