1. Department of Radiology, Obstetrics and Gynecology Hospital, Fudan University, Shanghai, P.R. China
2. Department of Radiology, Shanghai First Maternity and Infant Health Hospital, School of Medicine, Tongji University, Shanghai, P.R.China
3. Department of Information Technology, Obstetrics and Gynecology Hospital, Fudan University, Shanghai, P.R. China
4. Department of Obstetrics, Obstetrics and Gynecology Hospital, Fudan University, Shanghai, P.R. China
5. Department of Ultrasound, Obstetrics and Gynecology Hospital, Fudan University, Shanghai, P.R. China