1. Queen Mary University, London E1 4NS, UK
2. Centre for Reproductive Medicine, St. Bartholomew’s Hospital, London EC1A 7BE, UK
3. Hewitt Fertility Centre, Liverpool Women’s Hospital, Liverpool L8 7SS, UK
4. Centre for Women’s Health, Queen Mary University of London, E1 2AB, UK
5. Homerton University Hospital, London E9 6SR, UK
6. Department of Obstetrics and Gynecology, Penn State University College of Medicine, USA
7. Monash University, Clayton, VIC 3800, Australia
8. Monash Centre for Health Research and Implementation, Monash University, Clayton, VIC 3800, Australia
9. Tommy’s National Centre for Miscarriage Research, Institute of Metabolism and Systems Research, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
10. Birmingham Women’s and Children’s NHS Foundation Trust, Birmingham, UK
11. CIBER Epidemiology and Public Health, Clinical Biostatistics Unit, Hospital Ramon y Cajal Ctra, Madrid 28034, Spain
12. Women's Health Research Unit, Queen Mary University of London
13. Institute of Metabolism and Systems Research, University of Birmingham, Edgbaston, Birmingham B15 2TT UK