1. Department of Obstetrics and Gynecology, West China Second University Hospital of Sichuan University and the Key Laboratory of Birth Defects and Related Diseases of Women and ChildrenSichuan University, Ministry of Education Sichuan China
2. West China School of MedicineSichuan University Sichuan China
3. Department of RadiologyWest China Second University Hospital, Sichuan University Sichuan China
4. West China School of Public HealthSichuan University Sichuan China