1. Department of Gynecology, Beijing Obstetrics and Gynecology Hospital Capital Medical University Beijing China
2. Beijing Maternal and Child Health Care Hospital Beijing China
3. School of Medicine Tsinghua University Beijing China
4. Institute for Immunology and School of Medicine Tsinghua University Beijing China
5. Tsinghua‐Peking Center for Life Sciences Beijing China
6. Beijing Key Laboratory for Immunological Research on Chronic Diseases Beijing China