1. Department of Obstetrics and Gynecology, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, China
2. The First Affiliated Hospital, Department of Obstetrics and Gynecology, Hengyang Medical School, University of South China, Hengyang, Hunan, China
3. The Hospital Management Institute of University of South China, Hengyang, Hunan, China
4. The First Affiliated Hospital, Department of Oncology, Hengyang Medical School, University of South China, Hengyang, Hunan, China