1. Department of Obstetrics and Gynecology, Chang Gung Memorial Hospital, Taipei, Taiwan, College of Medicine, Chang Gung University, Tao-yuan, Taiwan
2. Department of Physical Medicine and Rehabilitation, Cheng Hsin Medical Center, Taipei, Taiwan
3. Department of Obstetrics and Gynecology, Chang Gung Memorial Hospital, Taipei, Taiwan
4. Department of Obstetrics and Gynecology, Chang Gung Memorial Hospital, Taipei, Taiwan, , College of Medicine, Chang Gung University, Tao-yuan, Taiwan