1 Department of Philosophy, King's College London, London, UK elselijn.kingma@kcl.ac.uk.
2 Amsterdam University Medical Centre (UMC), Vrije Universiteit Amsterdam, Department of Midwifery Science, AVAG, Amsterdam Public Health research institute, Amsterdam, The Netherlands.
3 Division of Midwifery, School of Health Sciences, University of Nottingham, Nottingham, UK.
4 Department of Obstetrics and Gynaecology, Maxima Medical Centre, Veldhoven, The Netherlands.
5 Amalia Children's Hospital, Department of Obstetrics, Radboud University Medical Center, Nijmegen, The Netherlands.
6 Amsterdam University Medical Centre (UMC), Vrije Universiteit Amsterdam, Department of Midwifery Science, AVAG, The Amsterdam Reproduction & Development research institute, Amsterdam, The Netherlands.
7 Department of General Practice & Elderly Medicine, Midwifery Science, University Medical Center (UMC) Groningen, University of Groningen, Groningen, The Netherlands.