1. Department of Obstetrics and Gynecology, Key Laboratory of Birth Defects and Related Diseases of Women and Children, Ministry of Education, West China Second University Hospital Sichuan University Sichuan P. R. China
2. Department of Forensic Genetics, West China School of Basic Medical Sciences and Forensic Medicine Sichuan University Sichuan P. R. China
3. Laboratory of Molecular Translational Medicine, Center for Translational Medicine, Department of Obstetrics and Gynecology Key Laboratory of Birth Defects and Related Diseases of Women and Children, Ministry of Education West China Second University Hospital Sichuan P. R. China
4. Department of Ultrasonography, Key Laboratory of Birth Defects and Related Diseases of Women and Children, Ministry of Education, West China Second University Hospital Sichuan University Sichuan P. R. China