1. Department of Gynecology and Obstetrics Tianjin Medical University General Hospital Tianjin China
2. Tianjin Key Laboratory of Female Reproductive Health and Eugenics Tianjin China
3. Department of Pathology First Teaching Hospital of Tianjin University of Traditional Chinese Medicine Tianjin China
4. Department of Gynecology and Obstetrics Nankai University Affiliated Hospital (Tianjin Fourth Hospital) Tianjin China