1 Department of Obstetrics and Gynecology, University of Foggia, Azienda Ospedaliero-Universitaria "Ospedali Riuniti", Foggia, Italy.
2 Department of Metabolism, Digestion and Reproduction, Institute of Reproductive and Developmental Biology, Imperial College London, London, UK.
3 Centre for Fetal Care, Queen Charlotte's and Chelsea Hospital, Imperial College Healthcare NHS Trust, London, UK.
4 Ultrasound and Underwater Acoustics Group, National Physical Laboratory, London, UK.
5 Department of Women and Children's Health, School of Life Course and Population Sciences, Faculty of Life Sciences & Medicine, King's College London, London, UK.
6 Physics Department, The Institute of Cancer Research, London, UK.
7 Department of Medicine and Surgery, Obstetrics and Gynecology Unit, University of Parma, Parma, Italy.