1. Department of Cadre Health Care, Anqing Municipal Hospital, Anhui Province, Anqing, China
2. Department of Obstetrics and Gynecology, Anqing Municipal Hospital, Anhui Province, Anqing, China
3. Department of Obstetrics and Gynecology, Anqing Municipal Hospital, Anhui Province, Anqing, China.
4. Department of Obstetrics and Gynecology, Anqing Municipal Hospital, Anhui Province, Anqing, China;, Email: liqing03027@163.com