1. Department of Gynecology, Zhejiang Provincial People's Hospital, People's Hospital of Hangzhou Medical College, Hangzhou, Zhejiang 310014, P.R. China
2. Department of Gynecology, The Affiliated Hospital of Hangzhou Normal University, Hangzhou, Zhejiang 310015, P.R. China
3. Reproductive Genetic Center, Suzhou Municipal Hospital, Suzhou Hospital of Nanjing, Nanjing, Jiangsu 215000, P.R. China
4. Department of Gynecology, The Second Affiliated Hospital, Nanjing Medical University, Nanjing, Jiangsu 210011, P.R. China