1. Department of Urology Peking University Third Hospital Beijing China
2. Peking University Health Science Center Beijing China
3. Research Center of Clinical Epidemiology Peking University Third Hospital Beijing China
4. Center for Reproductive Medicine, Department of Obstetrics and Gynecology Peking University Third Hospital Beijing China
5. National Clinical Research Center for Obstetrics and Gynecology (Peking University Third Hospital) Beijing China
6. Key Laboratory of Assisted Reproduction (Peking University), Ministry of Education Beijing China
7. Beijing Key Laboratory of Reproductive Endocrinology and Assisted Reproductive Technology Beijing China