1. Department of Obstetrics and Gynecology, Sancaktepe Sehit Prof Dr Ilhan Varank Training and Research Hospital University of Health Sciences Istanbul Turkey
2. Fetal Medicine Unit St George's University Hospitals NHS Foundation Trust, University of London London UK
3. Department of Obstetrics and Gynecology School of Medicine, Koc University Istanbul Turkey
4. Royal College of Obstetricians and Gynaecologists London UK
5. University College London Hospitals, Institute for Women's Health London UK
6. Institute of Women and Children's Health School of Life Course and Population Sciences, King's College London London UK
7. Department of Statistics, Faculty of Arts and Sciences Middle East Technical University Ankara Turkey
8. Twins Trust Centre for Research and Clinical Excellence St George's University Hospitals NHS Foundation Trust London UK
9. Vascular Biology Research Centre Molecular and Clinical Sciences Research Institute, St George's University of London London UK