1. Centre for Human Development, Stem Cells and Regeneration, School of Human Development and Health, Faculty of Medicine, University of Southampton , Southampton, UK
2. NIHR Southampton Biomedical Research Centre, University Hospital Southampton NHS Foundation Trust and University of Southampton , Southampton, UK
3. Complete Fertility Centre, Department of Obstetrics & Gynaecology, Princess Anne Hospital , Southampton, UK
4. Department of Obstetrics and Gynaecology, University Hospital Southampton NHS Foundation Trust , Southampton, UK
5. Medical Statistics, School of Primary Care, Population Sciences and Medical Education, Faculty of Medicine, University of Southampton , Southampton, UK
6. London Women’s Clinic , London, UK