1. Department of Obstetrics and Gynecology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China;
2. Prenatal Diagnosis Center, Shenzhen Maternity and Child Healthcare Hospital, henzhen, Guangdong Province, China;
3. Ultrasound Department, Shenzhen Maternity and Child Healthcare Hospital, Shenzhen, Guangdong Province, China;
4. AmCare Genomics Laboratory, International BioIsland, Guangzhou, Guangdong, China