1. Graduate School of Xuzhou Medical University, Huaihai West Road No. 84, Xuzhou, Jiangsu, China
2. Department of Prenatal Diagnosis Medical Center, Xuzhou Central Hospital, Xuzhou Clinical School of Xuzhou Medical University, Jiefang South Road No. 199, Xuzhou, Jiangsu, China
3. Department of Gynecology and Obstetrics, Pizhou People’s Hospital, Nanjing Road No. 9, Pizhou, Jiangsu, China
4. Graduate School of Bengbu Medical College, Donghai Avenue No. 2600, Bengbu, Anhui, China