1. Hebei Medical University, Shijiazhuang City, Hebei Province, 050017, China
2. Chengde Central Hospital, No. 11, Guangren Street, Shuangqiao District, Chengde City, Hebei Province, 050000, China
3. Department of Gynecology, The Fourth Hospital, Hebei Medical University, Changan District, Shijiazhuang City, Hebei Province, 067000, China
4. Chengde Medical University, Shuangqiao District, Chengde City, Hebei Province, 067000, China
5. Affiliated Hospital of Chengde Medical University, No. 36, Nanyingzi Street, Shuangqiao District, Chengde City, Hebei Province, 067000, China