1 Obstetrics Department, First Affiliated Hospital of Guizhou University of Traditional Chinese Medicine, Guiyang, Guizhou 550001, China.
2 Center for Eugenics Research, First Affiliated Hospital of Guizhou University of Traditional Chinese Medicine, Guiyang, Guizhou 550001, China.
3 Department of Clinical Laboratory, First Affiliated Hospital of Guizhou University of Traditional Chinese Medicine, Guiyang, Guizhou 550001, China.
4 Department of Prenatal Diagnostic Center, Guangzhou Women and Children's Medical Centre, Guangzhou Medical University, Guangzhou, Guangdong 511436, China.
5 Department of Prenatal Diagnosis Center, Guizhou Provincial People's Hospital, The Affiliated Hospital of Guizhou University, Guiyang, Guizhou 550002, China.