1. Department of PediatricsObstetrics and Gynecology Hospital Affiliated to Nanjing Medical UniversityNanjing210004China
2. Fourth Clinical Medicine CollegeNanjing Medical UniversityNanjing210029China
3. Department of ObstetricsObstetrics and Gynecology Hospital Affiliated to Nanjing Medical UniversityNanjing210004China
4. Department of UltrasoundObstetrics and Gynecology Hospital Affiliated to Nanjing Medical UniversityNanjing210004China
5. Department of Prenatal DiagnosisObstetrics and Gynecology Hospital Affiliated to Nanjing Medical UniversityNanjing210004China