The majority of women who planned to give birth at a tertiary-level maternity unit actually gave birth there (98%), with 28 women (0.9%) giving birth before arriving. Thirty-four women (1.1%) who intended to give birth at a tertiary-level maternity unit actually gave birth at a freestanding midwifery unit, and four of these women transferred to a tertiary-level maternity selleck unit postnatally. Figure 1 Study population and transfers from freestanding midwifery

units (FMU) to tertiary level maternity unit (TMU). Percentages expressed by planned place of birth. Table 3 shows the mean age, mean parity, proportion of nulliparous women, ethnicity, smoking status, risk status at booking, risk status at the onset of labour and rates of previous caesarean section by planned place of birth. There was no significant difference in mean parity and proportion of nulliparous women in each group. Women who planned to give birth at a freestanding midwifery unit had a significantly higher mean age, and significantly fewer women from this group smoked, had a risk factor at the onset of labour or had experienced a previous caesarean section compared with women from the tertiary-level maternity

unit. There were 27 women from the freestanding midwifery unit group who had a risk factor at the time of booking. Women who identified as an Oceanic ethnicity (representing women born in Australia, New Zealand, Papua New Guinea, Fiji and Western Samoa) made up most of the tertiary-level maternity unit group (90.5%), while this ethnicity only represented

70.9% of the freestanding midwifery unit group. Table 3 Maternal characteristics by planned place of birth Primary and secondary maternal outcomes Table 4 describes the primary and secondary maternal outcomes and shows the unadjusted ORs and AORs of maternal outcomes by planned place of birth. After adjusting for maternal age, smoking status, parity, risk at the onset of labour, gestation at the time of birth and previous caesarean section, compared with the tertiary cohort, freestanding midwifery unit women were significantly more likely to have a spontaneous vaginal birth (AOR 1.57; 95% CI 1.20 to 2.06) and significantly less likely to have a caesarean section (AOR Brefeldin_A 0.65; 95% CI 0.48 to 0.88), including elective caesarean section (AOR 0.50; 95% CI 0.29 to 0.88). The reduction in the odds of women from the freestanding midwifery unit group having an instrumental delivery or intrapartum caesarean section lost significance when adjusted for confounding factors (AOR 0.79; 95% CI 0.53 to 1.17 and AOR 0.76; 95% CI 0.53 to 1.10, respectively; table 4). Table 4 Maternal outcomes by planned place of birth After adjusting for confounding factors, women who planned to give birth in a freestanding midwifery unit were twice as likely to have a spontaneous onset of labour (AOR 2.01; 95% CI 1.60 to 2.54) and significantly less likely to experience: induction (AOR 0.50; 95% CI 0.39 to 0.63), augmentation of labour (AOR 0.51; 95% CI 0.