1. Department of Internal Medicine, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing, China
2. Department of Laboratory Medicine, University of California San Francisco, San Francisco, CA, USA
3. Department of Endocrinology, Beijing Chao-yang Hospital, Capital Medical University, Beijing, China
4. Department of Laboratory Medicine, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing, China