Simulation in developing new instruments for operative vaginal birth

  • Stephen O'Brien

Student thesis: Doctoral ThesisDoctor of Philosophy (PhD)


Operative vaginal birth (OVB) remains, in skilled hands, the most efficient way of expediting birth in the second stage of labour and is associated with fewer poor maternal and neonatal outcomes. However, multiple factors including training requirements, patient perception and medico-legal pressures have resulted in a steady reduction in the proportion of births being expedited with OVB. The BD Odon Device is a new device for OVB which is envisaged to mitigate these pressures and reduce the number of Caesarean sections performed in the
second stage of labour. Before introduction into clinical practice, any new device must be thoroughly and systematically evaluated to determine how likely it is to be used effectively, repeatably and safely. In this thesis I present an approach to this problem specific to new devices for operative vaginal births.
Simulated operative vaginal births using the BD Odon Device demonstrated that the device sits on the fetal head in a repeatable, predictable and potentially safe way. The device generates more perineal distention than commonly used ventouse devices, and generates more pressure on the fetal head than ventouse, but less than forceps. It can be used intuitively by the majority of accoucheurs following brief structured training. This combination of features suggests that, with appropriate training, it may be used in a variety of healthcare settings (including areas where OVB is infrequently used) and generate beneficial outcomes for women and babies.
Date of Award19 Jun 2018
Original languageEnglish
Awarding Institution
  • The University of Bristol
SupervisorChristy Burden (Supervisor) & Dimitrios Siassakos (Supervisor)


  • Odon Device
  • Operative Birth

Cite this