1. Obstetrics and Gynegology, Chungbuk National University Hospital, Cheongju, The Republic of Korea;
2. Chungbuk National University Hospital, Cheongju, The Republic of Korea;
3. Department of Pathology, College of Medicine, Chungbuk National University, Cheongju, The Republic of Korea;
4. Department of Pathology and Translational Genomics, Sungkyunkwan University School of Medicine, Samsung Medical Center, Seoul, Korea