About the Authors

Philip J. Dutton

Affiliation Maternal and Fetal Health Research Centre, Manchester Academic Health Science Centre, University of Manchester, Manchester, United Kingdom

Lynne K. Warrander

Affiliation Maternal and Fetal Health Research Centre, Manchester Academic Health Science Centre, University of Manchester, Manchester, United Kingdom

Stephen A. Roberts

Affiliation Health Sciences – Methodology, Manchester Academic Health Science Centre, University of Manchester, Manchester, United Kingdom

Giovanna Bernatavicius

Affiliation Department of Obstetrics, St Mary's Hospital, Central Manchester University Hospitals NHS Foundation Trust, Manchester, United Kingdom

Louise M. Byrd

Affiliation Department of Obstetrics, St Mary's Hospital, Central Manchester University Hospitals NHS Foundation Trust, Manchester, United Kingdom

David Gaze

Affiliation Department of Chemical Pathology, St George's Hospital Medical School, London, United Kingdom

Josh Kroll

Affiliation Maternal and Fetal Health Research Centre, Manchester Academic Health Science Centre, University of Manchester, Manchester, United Kingdom

Rebecca L. Jones

Affiliation Maternal and Fetal Health Research Centre, Manchester Academic Health Science Centre, University of Manchester, Manchester, United Kingdom

Colin P. Sibley

Affiliation Maternal and Fetal Health Research Centre, Manchester Academic Health Science Centre, University of Manchester, Manchester, United Kingdom

J. Frederik Frøen

Affiliation Division of Epidemiology, Norwegian Institute of Public Health, Oslo, Norway

Alexander E. P. Heazell

alexander.heazell@manchester.ac.uk

Affiliations Maternal and Fetal Health Research Centre, Manchester Academic Health Science Centre, University of Manchester, Manchester, United Kingdom, Department of Obstetrics, St Mary's Hospital, Central Manchester University Hospitals NHS Foundation Trust, Manchester, United Kingdom

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

Conceived and designed the experiments: AH SR LB RJ CS JF. Performed the experiments: AH LW RJ GB PD DG. Analyzed the data: AH SR. Contributed reagents/materials/analysis tools: DG AH CS. Wrote the paper: PD LW SR GB LB DG RJ JK CS JF AH. Database management and data validation: JK.