1. The Reproduction Center, The Third Affiliated Hospital of Zhengzhou University, Zhengzhou, People’s Republic of China
2. Department of General Surgery, Henan Provincial People's Hospital, Department of General Surgery of Central China Fuwai Hospital, Central China Fuwai Hospital of Zhengzhou University, Zhengzhou, Henan, China
3. Gynaecology and Obstetrics, The Fifth Peoples’ Hospital of Zhengzhou, Zhengzhou, People's Republic of China