1. Department of Obstetrics and Gynecology Research Institute of Medical Science, Konkuk University School of Medicine Seoul Republic of Korea
2. Department of Obstetrics and Gynecology Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine Seoul Republic of Korea
3. Department of Obstetrics and Gynecology Soonchunhyang University Cheonan Hospital Cheonan Republic of Korea
4. Department of Obstetrics and Gynecology Hosan Women's Hospital, Gangnam‐gu Seoul Republic of Korea