Caesarean section rates: applying the modified ten-group Robson classification in an Australian tertiary hospital.

The aim of this study was to determine the main contributors to caesarean section (CS) rates at an Australian tertiary hospital. We conducted a retrospective review of women who delivered in an Australian tertiary hospital between 2014 and 2017. Women were allocated according to a modified Robson Ten-Group Classification System and CS indications were collected in nulliparous women and women with previous CS. The largest contributor to the 35.7% overall CS rate was women with a term cephalic infant and a previous CS (31.5% relative CS rate) and the most common indication was repeat CS. The group CS rate in nulliparous women with a cephalic term infant was higher when labour was induced compared to occurring spontaneously (36.6% and 18.1% respectively). The primary CS indication for these women was labour dystocia and maternal request was the most common CS indication for nulliparous women with a pre-labour CS.IMPACT STATEMENT Significantly increasing caesarean section (CS) rates continue to prompt concern due to the associated neonatal and maternal risks. The World Health Organisation have endorsed the Robson Ten-Group Classification System to identify and analyse CS rate contributors. We have used the modified Robson Ten-Group Classification System to identify that women with cephalic term infants who are nulliparous or who have had a previous CS are the largest contributors to overall CS rates. CS rates were higher in these nulliparous women if labour was induced compared to occurring spontaneously and the primary CS indication was labour dystocia. In nulliparous women with a CS prior to labour the most common CS indication was maternal request. Majority of women with a previous CS elected for a repeat CS. Future efforts should focus on minimising repeat CS in multiparous women and primary CS in nulliparous women. This may be achieved by redefining the definition of labour dystocia, exploring maternal request CS reasoning and critically evaluating induction timing and indication. Appropriately promoting a trial of labour in women with a previous CS in suitable candidates may reduce repeat CS incidence.