Results There were 250 primary outcome events and an overall weighted
incidence of 4.3 per 1000 births (95% CI 3.3 to 5.5). Overall, there were
no significant differences in the adjusted odds of the primary outcome
for any of the non-obstetric unit settings compared with obstetric units.
For nulliparous women, the odds of the primary outcome were higher
for planned home births (adjusted odds ratio 1.75, 95% CI 1.07 to 2.86)
but not for either midwifery unit setting. For multiparous women, there
were no significant differences in the incidence of the primary outcome
by planned place of birth. Interventions during labour were substantially
lower in all non-obstetric unit settings. Transfers from non-obstetric unit
settings were more frequent for nulliparous women (36% to 45%) than
for multiparous women (9% to 13%).