1. Department of Obstetrics and Gynecology, Chang Gung Memorial Hospital Linkou Medical Center, Chang Gung University College of Medicine, Taoyuan, Taiwan
2. Department of Obstetrics and Gynecology, Taipei City Hospital, Women and Children Campus, Taipei, Taiwan
3. Department of Biomedical Engineering, National Yang Ming University, Taipei, Taiwan
4. Department of Obstetrics, Shanghai First Maternity and Infant Hospital, Tongji University School of Medicine, Shanghai, China