1. Center for Reproductive Medicine, Ren Ji Hospital School of Medicine, Shanghai Jiao Tong University Shanghai P.R. China
2. Shanghai Key Laboratory for Assisted Reproduction and Reproductive Genetics Shanghai P.R. China
3. Department of Obstetrics and Gynecology Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University Shanghai P.R. China
4. Shanghai First Maternity and Infant Hospital Tongji University School of Medicine Shanghai P.R. China
5. Department of Obstetrics and Gynecology Oregon Health and Science University Portland Oregon USA