1. Department of Gynecology, The First Affiliated Hospital of China Medical University, Shenyang, Liaoning 110001, P.R. China
2. Department of Gynecology and Obstetrics, Union Hospital Affiliated to Tongji Medical College Huazhong University of Science and Technology, Wuhan, Hubei 430022, P.R. China
3. China Medical University, Shenyang, Liaoning 110122, P.R. China
4. Rehabilitation Center, Shengjing Hospital of China Medical University, Shenyang, Liaoning 110134, P.R. China