1. Department of Obstetrics and Gynecology, Korea University Guro Hospital, Seoul, Korea.
2. Department of Obstetrics and Gynecology, Graduate School of Medicine, Kangwon National University, Chuncheon, Korea.
3. National Evidence-based Healthcare Collaborating Agency (NECA), Seoul, Korea.
4. Department of Obstetrics and Gynecology, CHA Gangnam Medical Center, Seoul, Korea.
5. Department of Obstetrics and Gynecology, Korea University Anam Hospital, Seoul, Korea.
6. Department of Obstetrics and Gynecology, Keimyung University Dongsan Medical Center, Daegu, Korea.
7. Department of Obstetrics and Gynecology, Konkuk University Hospital, Seoul, Korea.
8. Department of Obstetrics and Gynecology, Chungnam National University Hospital, Daejeon, Korea.
9. Department of Obstetrics and Gynecology, Seoul National University Hospital, Seoul, Korea.
10. Department of Obstetrics and Gynecology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea.
11. Department of Obstetrics and Gynecology, Yonsei University Severance Hospital, Seoul, Korea.
12. Department of Obstetrics and Gynecology, Dankook University Hospital, Dankook University, Cheonan, Korea.
13. Department of Obstetrics and Gynecology, Kyungpook National University Chilgok Hospital, Daegu, Korea.
14. Comprehensive Gynecologic Cancer Center, CHA Bundang Medical Center, Seongnam, Korea.
15. Department of Obstetrics and Gynecology, Samsung Medical Center, Seoul, Korea.
16. Department of Obstetrics and Gynecology, Korea University Ansan Hospital, Ansan, Korea.