In 2019, about 2 in 5 (42.5%) mothers who gave birth had a spontaneous labour, around 1 in 3 (35%) had induced labour and 1 in 5 had no labour (23%).
Labour onset varied by maternal age group. Teenage mothers (aged under 20) were the most likely to have spontaneous labour (55%), and mothers aged 40 or over were the most likely to have no labour onset (43%).
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 (57%) than women with a singleton pregnancy (22%).
The rate of spontaneous labour has fallen (from 56% in 2009 to 42.5% in 2019) with corresponding increases in the rates of induced labour (from 25% to 35%) and no labour (from 18% to 23%).
For related information see National Core Maternity Indicator Induction of labour
For mothers whose labour was induced, a combination of medical and/or surgical types of induction were most commonly used. Data excludes Western Australia.
In 2019, the main reasons for inducing labour were diabetes (14%), pre-labour rupture of membranes (10%) and prolonged pregnancy (8%).
Augmentation of labour
Once labour starts, it may be necessary to intervene to speed up or augment the labour. Labour was augmented for 17% of mothers in 2019 (30% of mothers with spontaneous onset of labour). The augmentation rate was higher among first-time mothers, at 42% of those with spontaneous labour onset, compared with 21% of mothers who had given birth previously. Data excludes Western Australia.