1 Department of Obstetrics and Gynecology, The PLA Rocket Force Characteristic Medical Center, The Postgraduate Training Base of Jinzhou Medical University, Beijing, China.
2 Department of Women's Tumor, Anyang Tumor Hospital, Anyang, China.
3 Department of Obstetrics and Gynecology, Zhuozhou City's Hospital, Zhuozhou, China.
4 Department of Stomatology, Zhongshan College of Dalian Medical University, Dalian, China.
5 Department of Obstetrics and Gynecology, PLA Rocket Force Characteristic Medical Center, Beijing, China - Imhmm51@yeah.net.