1. Department of Medical Epidemiology and Biostatistics; Karolinska Institute; Stockholm Sweden
2. Reproductive Medicine; Department of Obstetrics and Gynecology; Karolinska University Hospital; Stockholm Sweden
3. Department of Oncology-Pathology; Karolinska Institute; Stockholm Sweden
4. Department of Women's and Children's Health; Karolinska Institute; Stockholm Sweden
5. Carl von Linné Clinic; Uppsala Sweden
6. Department of Women's and Children's Health; Uppsala University; Uppsala Sweden
7. Center for Reproductive Biology in Uppsala; University of Agricultural Sciences and Uppsala University; Uppsala Sweden
8. IVF-kliniken Stockholm, S:t Görans sjukhus; Stockholm Sweden
9. Fertilitetscentrum Stockholm; Stockholm Sweden
10. Clinical Epidemiology Unit; Department of Medicine Solna; Karolinska Institute; Stockholm Sweden