1. Department of Obstetrics and Gynecology; Oregon Health and Science University; Portland OR USA
2. Department of Obstetrics and Gynaecology, Faculty of Medicine and Health Sciences; University of Stellenbosch, Francie van Zyl Dr, Tygerberg Hospital, Bellville; Cape Town 7505 South Africa
3. Fertility Regulation Group; Oregon Health Sciences University; Portland OR USA
4. NHC Key Lab of Reproduction Regulation (Shanghai Institute for Biomedical and Pharmaceutical Technologies); Fudan University; Shanghai China
5. American Society for Emergency Contraception; Princeton NJ USA
6. Beth Israel Deaconess Medical Center; Boston MA USA