1. Department of Obstetrics and Gynecology, Chang Gung Memorial Hospital,Taipei and College of Medicine, Chang Gung University,Tao-yuan, Taiwan
2. Department of Obstetrics and Gynecology, Chang Gung Memorial Hospital,Taipei and College of Medicine, Chang Gung University,Tao-yuan, Taiwan; Department of Obstetrics and Gynecology, Chang Gung Memorial Hospital, 199 Dun-hua North Road, Taipei 105,Taiwan;