1. Beginning Assisted Conception Unit Epsom and St Helier University Hospitals London UK
2. Comprehensive Clinical Trials Unit Institute of Clinical Trials & Methodology, University College London London UK
3. Women's Health Department University College London Hospitals London UK
4. EGA Institute for Women’s Health Faculty of Population Health Sciences, University College London (UCL) London UK
5. MRC Clinical Trials Unit at UCL Institute of Clinical Trials & Methodology, University College London London UK