Institution: | 1. Department of Obstetrics and Gynecology, University of Inje College of Medicine, Haeundae Paik Hospital, Pusan, Korea;2. Department of Obstetrics and Gynecology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea;3. Department of Obstetrics and Gynecology, University of Ulsan College of Medicine, Ulsan University Hospital, Ulsan, Korea |