1. Department of Obstetrics and Gynecology, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea
2. Institute of Women’s Life Medical Science, Yonsei University College of Medicine, Seoul, Republic of Korea
3. Department of Obstetrics and Gynecology, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea
4. Department of Pathology, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea