1 Department of Gynecologic and Obstetric, The Affiliated Hospital of Inner Mongolia Medical University, Huhhot, 010050, China.
2 Department of Gynecologic and Obstetric, The Affiliated Hospital of Inner Mongolia Medical University, Huhhot, 010050, China. Electronic address: 90098687@sina.com.
3 Inner Mongolia Medical University, Department of Orthopedics, Affiliated Hospital of Inner Mongolia Medical University, Huhehot North Street, Inner Mongolia, 010050, China.