Method of birth

Two in 3 women in Australia had vaginal births, while the remaining 1 in 3 had a caesarean section birth. Mothers who had caesarean sections include all those who had no labour onset as well as those who required a caesarean section after labour started. For multiple births, women are categorised by the method of birth of the first-born baby.

Non-instrumental vaginal births were more common for women whose babies were born at term or post-term, who were teenage mothers (aged under 20) and who were underweight or normal weight. Caesarean sections were more common among women whose babies were pre-term, who were aged 40 and over and who were overweight and obese.

Instrumental vaginal births (vaginal birth assisted by forceps or vacuum extraction) decreased with increasing remoteness, and were more common among mothers in the highest socioeconomic areas. The rates for vaginal birth assisted by vacuum extraction decreased with increasing maternal age, whereas the rates for vaginal birth assisted by forceps peaked among women aged 25–29.

Internationally, the caesarean section rate has been increasing in most Organisation for Economic Cooperation and Development (OECD) countries, including Australia, and Australia’s rate of 34 per 100 live births is higher than the OECD average of 28 per 100 live births (OECD 2019).

While caesarean section is the most appropriate delivery method for many conditions and complications that can affect the mother and/or baby, the benefits need to be weighed against the risks (ACSQHC 2018). Risks to the mother include postoperative infection, haemorrhage and complications during future pregnancies. Risks to the baby include increased rates of asthma and obesity, and breathing difficulties and developmental issues in babies born by caesarean section at less than 39 weeks gestation (ACSQHC 2018).

Robson classification of caesarean sections

In 2015, the World Health Organization (WHO) recommended that the Robson 10 group classification system (Robson classification) be used to evaluate and compare caesarean section rates between groups of women (ACSQHC 2018; WHO RHR 2015).

The Robson classification allocates women into 10 mutually exclusive groups based on obstetric characteristics, such as the number of previous pregnancies, onset of labour, whether there has been a previous caesarean section, and the baby’s gestational age (WHO 2018; WHO RHR 2015). This can provide a more detailed understanding of the relatively high caesarean section rate in Australia and can be used to inform targeted intervention.

Hover over the graph to see the definition of each Robson group.

First-time mothers with a breech pregnancy (baby is delivered buttocks or feet first) (Robson group 6) were most likely to have a caesarean section, followed by mothers who have previously given birth with a breech pregnancy (Robson group 7) and those with singleton pregnancies near term who had had one or more previous caesarean sections (Robson group 5).

References

ACSQHC (Australian Commission on Safety and Quality in Health Care) 2018. The Second Australian Atlas of Healthcare Variation. Sydney: ACSQHC. Viewed 3 January 2018.

OECD (Organisation for Economic Co-operation and Development) 2019. Health at a glance 2019: OECD indicators. Paris: OECD Publishing. Viewed 1 April 2020.

WHO (World Health Organization) 2018. Robson classification: implementation manual. Geneva: WHO. Viewed 10 May 2018.

WHO RHR (Department of Reproductive Health and Research) 2015. WHO statement on caesarean section rates. WHO/RHR/15.02. Geneva: WHO. Viewed 21 November 2018.