1. Department of Obstetrics Gynecology and Reproductive Sciences Division of Reproductive Sciences Yale School of Medicine New Haven Connecticut USA
2. Institute of Reproductive Health Center for Reproductive Medicine Tongji Medical College Huazhong University of Science and Technology Wuhan P. R. China
3. C.S. Mott Center for Human Growth and Development Department of Obstetrics Gynecology, Wayne State University Detroit Michigan USA
4. Department of Obstetrics and Gynecology University of Helsinki and the Helsinki University Hospital Helsinki Finland
5. Department of Obstetrics and Gynecology North Zealand Hospital Hilleroed Denmark
6. Department of Biostatistics School of Public Health Yale University New Haven Connecticut USA
7. Department of Obstetrics Gynecology and Reproductive Sciences University of Miami Miller School of Medicine Miami Florida USA