Design
We conducted a retrospective cohort study examining all trials of operative vaginal delivery performed in Obstetric theatre at the James Cook University NHS Hospital over five years (2014-2018). The hospital is a consultant-led UK NHS maternity unit with between approximately 4500-5000 deliveries per year and level three neonatal intensive care facilities. Within the delivery unit there is consultant presence on labour ward from 0830-2200 every day with a senior registrar (doctor with minimum 5 years postgraduate obstetric training) present overnight. For all second stage of labour deliveries performed in obstetric theatre the unit policy recommends consultant attendance to supervise the delivery. Our study was granted ethical approval provided by the local learning and research institute as part of an ongoing service evaluation.