Anecdotally, it has been suggested that obstetricians of similar training and experience have different intervention rates on the labour ward. This phenomenon has not been studied in depth. The aim of this study was to record the intra-partum intervention rates for third on-call registrars and correlate this with the anxiety traits of the corresponding registrars. An analysis of births occurring during out-of-hours in the main delivery unit of a large teaching hospital during the period September 2005-September 2006 was carried out. The rate of interventions per cumulative number of deliveries that occurred specific to each doctor on-call was calculated. Anxiety traits were calculated with a validated questionnaire. There is a significant difference in the caesarean section rates between registrars of similar experience. There is also a strong correlation between the registrar's anxiety trait level and the registrar's emergency caesarean section rates (Pearsons correlate 0.722, p<0.01).