1. Department of Obstetrics and Gynecology, Jiangmen Central Hospital, Jiangmen, Guangdong Province, People’s Republic of China
2. Tianjin Medical Laboratory, BGI-Tianjin, BGI-Shenzhen, Tianjin, Tianjin Municipality, People’s Republic of China
3. Department of Obstetrics and Gynecology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, Chongqing Municipality, People’s Republic of China
4. BGI Genomics, BGI-Shenzhen, Shenzhen, Guangdong Province, People’s Republic of China