1. Department of Obstetrics and Gynecology, Hallym University College of Medicine, Kangnam Sacred Heart Hospital, Seoul 07441, Republic of Korea
2. Department of Obstetrics and Gynecology, Chungnam National University Hospital, Daejeon 35015, Republic of Korea
3. Institute of New Frontier Research Team, College of Medicine, Hallym University, Chuncheon 24252, Republic of Korea