1. Division of Developmental Biology and Medicine, Maternal and Fetal Health Research Centre, School of Medical Sciences, Faculty of Biology, Medicine and Health University of Manchester Manchester UK
2. University of Groningen Groningen The Netherlands
3. Department of Gynaecology Leiden University Medical Centre Leiden The Netherlands
4. National Perinatal Epidemiology Unit, Nuffield Department of Population Health University of Oxford Oxford UK
5. University of Nottingham Nottingham UK
6. Saint Mary's Hospital Manchester University NHS Foundation Trust Manchester UK
7. Department of Gynaecology Saxenburgh Medisch Centrum Hardenberg The Netherlands
8. Department of Anaesthesia, Wythenshawe Hospital Manchester University NHS Foundation Trust Manchester UK
9. Lancaster Medical School Lancaster University Lancaster UK