Australia's mothers and babies

Labour can occur spontaneously or may be induced by medical or surgical intervention. Examples of medical inductions are oxytocin and prostaglandins, examples of surgical inductions are artificial rupture of membranes and mechanical cervical dilation. Some women don’t have labour, such as when a caesarean section is performed before the onset of labour or a failed induction of labour.

Induction of labour is performed for a number of reasons related to both the mother and the baby, such as maternal or baby medical conditions and post-term pregnancy (Coates et al. 2020). Whilst most women who have induced labour – and their babies – do well, induction of labour increases the risk of infection and bleeding, and women reporting a less positive birth experience when compared to spontaneous labour (Coates et al. 2020; Grivell et al. 2012). There is evidence that induction also increases the risk of emergency caesarean section (Coates et al. 2020; Grivell et al. 2012). However, some recent research suggests that induction of labour may not increase the risk of caesarean section in certain cases (Grobman et al. 2018; Middleton et al. 2020; RANZCOG 2021).

Between 2010 and 2023, there was a shift in the occurrence of the different types of labour onset, the rate of spontaneous labour decreased (56% and 40%, respectively)  while the rate of induced labour (25% to 33%, respectively) and no labour (19% to 27%, respectively) both increased. In the last few years, the rate of induced labour has shown a slight decrease from 36% in 2020.

Figure 1 presents trend data on the onset of labour of women who gave birth, by selected maternal characteristics, between 2010 (or earliest available year of data) and 2023. Select the ‘Current data’ button to view 2023 data.

In 2023, labour onset varied by maternal age group. Mothers aged under 20 were the most likely to have spontaneous labour (50%), and mothers aged 40 or over were the most likely to have no labour onset (47%).

Onset of labour varied considerably by the number of babies born from a single pregnancy, with women who had a multiple pregnancy being more likely to have no labour (60%) than women with a singleton pregnancy (26%).

Labour onset also varied by maternal country of birth. Women born in Nepal were the most likely to have induced labour (42%) and women born in Vietnam (48%), New Zealand (45%) and the Philippines (44%) were the most likely to have spontaneous labour. Women born in South Africa and China were the most likely to have no labour onset (both 35%).

Induction type and reason

For mothers whose labour was induced, oxytocin was most commonly used (76 per 100 women who gave birth and had an induction). Noting that a combination of medical and/or surgical types of induction can be reported.

In 2023, the main reasons for inducing labour were diabetes (15%), pre-labour rupture of membranes (11%) and prolonged pregnancy (10%).

Augmentation of labour

Once labour starts, it may be necessary to intervene to speed up or augment the labour. In 2023, labour was augmented for 27% of mothers with spontaneous onset of labour (15% of all mothers). For mothers with spontaneous labour onset, the augmentation rate was higher among first-time mothers (38%) than among mothers who had given birth previously 18%. Data excludes Western Australia.