About the Authors

Manisha Nair

manisha.nair@npeu.ox.ac.uk

Affiliation National Perinatal Epidemiology Unit, Nuffield Department of Population Health, University of Oxford, Oxford, United Kingdom

Jennnifer J. Kurinczuk

Affiliation National Perinatal Epidemiology Unit, Nuffield Department of Population Health, University of Oxford, Oxford, United Kingdom

Marian Knight

Affiliation National Perinatal Epidemiology Unit, Nuffield Department of Population Health, University of Oxford, Oxford, United Kingdom

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

Conceived and designed the experiments: MK. Analyzed the data: MN. Contributed reagents/materials/analysis tools: JK MK. Wrote the paper: MN JK MK.