[1] Chung Shan Med Univ, Inst Med, 110,Sec 1,Jianguo N Rd, Taichung 40201, Taiwan
[2] Hsinchu MacKay Mem Hosp, Dept Obstet & Gynecol, Hsinchu, Taiwan
[3] Mackay Med Coll, New Taipei, Taiwan
[4] Lee Womens Hosp, Dept Obstet & Gynecol, Taichung, Taiwan
[5] Mackay Jr Coll Med Nursing & Management, Taipei, Taiwan
[6] China Med Univ Hosp, Dept Obstet & Gynecol, Taichung, Taiwan
[7] Natl Taiwan Normal Univ, Dept Math, Taipei, Taiwan
[8] Chung Shan Med Univ Hosp, Dept Obstet & Gynecol, Taichung, Taiwan