Affiliation: | a Department of Obstetrics and Gynecology, Taichung Veterans General Hospital, Chung-Shan Medical University, Taichung, Taiwanb Department of Obstetrics and Gynecology, Hung-Kuang University, Taichung, Taiwanc Department of Obstetrics and Gynecology, Institute of Clinical Medicine, National Yang-Ming University, Taipei, Taiwan |