1. Department of Obstetrics and Gynecology, Reproductive Medicine Center, The Affiliated Hospital of Guizhou Medical University, Guiyang, Guizhou 550004, P.R. China
2. Department of Obstetrics and Gynecology, The Affiliated Hospital of Guizhou Medical University, Guiyang, Guizhou 550004, P.R. China
3. Department of Obstetrics and Gynecology, Guizhou Medical University, Guiyang, Guizhou 550004, P.R. China
4. Department of Gastroenterology, Second Affiliated Hospital, Shantou University Medical College, Shantou, Guangdong 515041, P.R. China
5. Department of Urinary Surgery, The Affiliated Hospital of Guizhou Medical University, Guiyang, Guizhou 550004, P.R. China
6. Department of Psychology, The Affiliated Hospital of Guizhou Medical University, Guiyang, Guizhou 550004, P.R. China