Fa-Kung Lee1, Ming-Shyen Yen2, Peng-Hui Wang3. 1. Department of Obstetrics and Gynecology, Cathay General Hospital, Taipei, Taiwan. 2. Department of Obstetrics and Gynecology, Taipei Veterans General Hospital, Taipei, Taiwan; Department of Obstetrics and Gynecology, National Yang-Ming University, Taipei, Taiwan; Institute of Clinical Medicine, National Yang-Ming University, Taipei, Taiwan; Department of Medical Research, China Medical University Hospital, Taichung, Taiwan. 3. Department of Obstetrics and Gynecology, Taipei Veterans General Hospital, Taipei, Taiwan; Department of Obstetrics and Gynecology, National Yang-Ming University, Taipei, Taiwan; Institute of Clinical Medicine, National Yang-Ming University, Taipei, Taiwan; Department of Medical Research, China Medical University Hospital, Taichung, Taiwan. Electronic address: phwang@vghtpe.gov.tw.