1. Department of Clinical Research; Vendsyssel Hospital; Hjørring Denmark
2. Department of Obstetrics and Gynecology; Aalborg University Hospital; Aalborg Denmark
3. The Fertility Clinic; University Hospital Copenhagen; Copenhagen Denmark
4. Department of Obstetrics and Gynecology; Aarhus University Hospital; Aarhus Denmark
5. Department of Obstetrics; Rigshospitalet University Hospital; University of Copenhagen; Copenhagen Denmark