1. University of Southampton, Human Development and Health, Southampton, UK
2. University of Southampton, Complete Fertility, Princess Anne Hospital, Southampton, UK
3. University of Sheffield, Academic Unit of Medical, Sheffield, UK
4. University of Sheffield, Sheffield Teaching Hospitals NHS Foundation Trust, Obstetrics and Gynaecology, Sheffield, UK
5. University of Southampton, Institute for Life Sciences, Southampton, UK
6. University of Aberdeen, Obstetrics and Gynaecology, Aberdeen, UK
7. Chinese University of Hong Kong, Department of Obstetrics and Gynaecology, Shatin, Hong Kong