1. Division of Reproductive Sciences Department of Obstetrics, Gynecology and Reproductive Sciences Yale School of Medicine New Haven CT USA
2. Department of Obstetrics and Gynecology University of Helsinki and The Helsinki University Hospital Helsinki Finland
3. Department of Obstetrics and Gynecology North Zealand Hospital Hilleroed Denmark
4. Department of Biostatistics School of Public Health Yale University New Haven CT USA
5. Department of Obstetrics, Gynecology and Reproductive Sciences University of Miami Miller School of Medicine Miami FL USA
6. Department of Obstetrics and Gynecology C.S. Mott Center for Human Growth and Development Wayne State University Detroit MI USA