1. Department of Rehabilitation Medicine, Konkuk University Medical Center and Konkuk University School of Medicine, Konkuk University: 120-1 Neungdong-Ro, Gwangjin-Gu, Seoul 143-729, Republic of Korea
2. Department of Obstetrics and Gynecology, Konkuk University Medical Center and Konkuk University School of Medicine, Konkuk University, Republic of Korea