Table 1 Perinatal and sociodemographic data compared between Aboriginal and non-Aboriginal births

In-utero transfer

26 (12.1%)

1345 (3.5%)

2.49, 5.73

Maternal age (years) – mean (SD)

27.4 (6.7)

30.7 (5.2)

−3.7, − 2.0

Maternal age < 20 years

21 (9.8%)

628 (1.6%)

3.54, 9.24

BMI > 25

115/192 (59.9%)

15,622/36682 (42.6%)

1.39, 2.56

Diabetes

33 (15.3%)

2802 (7.3%)

1.59, 3.35

Smoking (any)

123/210 (58.6%)

4070/38036 (10.7%)

8.16, 14.5

Smoking throughout pregnancy

113/210 (53.8%)

2123/38036 (5.6%)

12.8, 23.0

Drug use

57 (26.5%)

916 (2.4%)

10.4, 19.6

Alcohol use

14 (6.5%)

237 (0.6%)

6.38, 19.4

Mental health diagnosis

106/214 (49.5%)

7185/38144 (18.8%)

2.86, 4.97

APH

24 (11.2%)

1870 (4.9%)

1.57, 3.68

Pre-eclampsia/HELLP

9 (4.2%)

791 (2.1%)

1.06, 4.03

UTI in pregnancy

2 (0.9%)

188 (0.5%)

0.48, 7.79

Hypertension^c

14 (6.5%)

1369 (3.6%)

0.98, 3.25

Male sex

123 (57.2%)

19,681 (51.6%)

0.96, 1.64

Birthweight (g) – mean (SD)

3036 (893)

3320 (607)

−413, −166

High birthweight > 4000 g

17 (7.9%)

3763 (9.9%)

0.46, 1.31

Low birthweight < 2500 g

48 (22.3%)

2576 (6.7%)

2.90, 5.60

Very low birthweight < 1500 g

21 (9.8%)

701 (1.8%)

3.67, 9.16

Gestational age (weeks) – mean (SD)

37.3 (3.9)

38.8 (2.3)

−2.1, − 1.1

Preterm < 37 weeks

50 (23.3%)

3002 (7.9%)

2.58, 4.95

Birthweight z-score – mean (SD)

−0.04 (1.14)

− 0.06 (0.93)

− 0.13, 0.19