Objectives To compare the risk profile of women giving birth in private and public hospitals and the rate of obstetric intervention during birth compared with previous published rates from a decade ago.

Design Population-based descriptive study.

Setting New South Wales, Australia.

Participants 691 738 women giving birth to a singleton baby during the period 2000 to 2008.

Main outcome measures Risk profile of women giving birth in public and private hospitals, intervention rates and changes in these rates over the past decade.

Results Among low-risk women rates of obstetric intervention were highest in private hospitals and lowest in public hospitals. Low-risk primiparous women giving birth in a private hospital compared to a public hospital had higher rates of induction (31% vs 23%); instrumental birth (29% vs 18%); caesarean section (27% vs 18%), epidural (53% vs 32%) and episiotomy (28% vs 12%) and lower normal vaginal birth rates (44% vs 64%). Low-risk multiparous women had higher rates of instrumental birth (7% vs 3%), caesarean section (27% vs 16%), epidural (35% vs 12%) and episiotomy (8% vs 2%) and lower normal vaginal birth rates (66% vs 81%). As interventions were introduced during labour, the rate of interventions in birth increased. Over the past decade these interventions have increased by 5% for women in public hospitals and by over 10% for women in private hospitals. Among low-risk primiparous women giving birth in private hospitals 15 per 100 women had a vaginal birth with no obstetric intervention compared to 35 per 100 women giving birth in a public hospital.

Conclusions Low-risk primiparous women giving birth in private hospitals have more chance of a surgical birth than a normal vaginal birth and this phenomenon has increased markedly in the past decade.