1. Centre for Fetal Care, Imperial College London, Queen Charlotte’s and Chelsea Hospital, Imperial College Healthcare National Health Service Trust, London, UK;
2. Department of Bioengineering, Imperial College London, London, UK;
3. Department of Mechanical Engineering, Imperial College London, London, UK;
4. Department of Obstetrics, University Medical Center Utrecht, Utrecht, The Netherlands;
5. Department of Development and Regeneration, KU Leuven, Belgium