1. Medical Research Center, State Key Laboratory of Complex Severe and Rare Diseases Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College Beijing China
2. School of Public Health Peking University Health Science Center Beijing China
3. Department of Epidemiology and Statistics Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and School of Basic Medicine, Peking Union Medical College Beijing China
4. Department of Gynaecology and Obstetrics Children's Hospital of Shanxi Province Shanxi China
5. Department of Gynaecology and Obstetrics Maternal and Child Health Hospital of Wuxi Jiangsu China
6. Department of Gynaecology and Obstetrics Maternal and Child Health Hospital of Gansu Province Lanzhou China
7. Department of Gynaecology and Obstetrics Maternal and Child Health Hospital of Foshan Guangdong China
8. Department of Gynaecology and Obstetrics Maternal and Child Health Hospital of Guiyang Guizhou China
9. Department of Gynaecology and Obstetrics Sheng Jing Hospital of China Medical University Liaoning China
10. Department of Gynecology and Obstetrics, State Key Laboratory of Complex Severe and Rare Diseases Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College Beijing China