| Affiliation: | 1. National Center for Birth Defect Monitoring, West China Second Hospital, Chengdu, China;2. Laboratory of Molecular Epidemiology for Birth Defects, West China Second Hospital, Chengdu, China;3. Department of Obstetrics and Gynecology, Sichuan University, Chengdu, China;4. Laboratory of Genetics, West China Second Hospital, Chengdu, China;5. Department of Ultrasound, Maternal and Child Health Hospital of Shenzhen, Shenzhen, China;6. Department of Ultrasound, Maternal and Child Health Hospital of Hubei, Wuhan, China;7. Department of Obstetrics and Gynecology, Maternal and Child Health Hospital of Fujian, Fuzhou, China |
