[1] Kyungpook National University Chilgok Hospital,Department of Obstetrics and Gynecology, School of Medicine
[2] Kyungpook National University,Department of Obstetrics and Gynecology
[3] Kyung Hee University School of Medicine,Department of Obstetrics and Gynecology
[4] Samsung Medical Center,Department of Obstetrics and Gynecology, Graduate School of Medicine
[5] Sungkyunkwan University School of Medicine,Department of Obstetrics and Gynecology
[6] Dongguk University,Department of Obstetrics and Gynecology, Institute of Women’s Life Medical Science
[7] Konkuk University Medical Center,undefined
[8] Konkuk University School of Medicine,undefined
[9] Yonsei University College of Medicine,undefined