Table 1.

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

Variable	Aboriginal n = 215	Non-Aboriginal n = 38,167	Statistics	95% CI	p-value
In-utero transfer	26 (12.1%)	1345 (3.5%)	3.77a	2.49, 5.73	< 0.001
Maternal age (years) – mean (SD)	27.4 (6.7)	30.7 (5.2)	−2.9b	−3.7, − 2.0	< 0.001
Maternal age < 20 years	21 (9.8%)	628 (1.6%)	5.72a	3.54, 9.24	< 0.001
BMI > 25	115/192 (59.9%)	15,622/36682 (42.6%)	1.88a	1.39, 2.56	< 0.001
Diabetes	33 (15.3%)	2802 (7.3%)	2.31a	1.59, 3.35	< 0.001
Smoking (any)	123/210 (58.6%)	4070/38036 (10.7%)	10.9a	8.16, 14.5	< 0.001
Smoking throughout pregnancy	113/210 (53.8%)	2123/38036 (5.6%)	17.2a	12.8, 23.0	< 0.001
Drug use	57 (26.5%)	916 (2.4%)	14.3a	10.4, 19.6	< 0.001
Alcohol use	14 (6.5%)	237 (0.6%)	11.1a	6.38, 19.4	< 0.001
Mental health diagnosis	106/214 (49.5%)	7185/38144 (18.8%)	3.77a	2.86, 4.97	< 0.001
APH	24 (11.2%)	1870 (4.9%)	2.40a	1.57, 3.68	< 0.001
Pre-eclampsia/HELLP	9 (4.2%)	791 (2.1%)	2.07a	1.06, 4.03	0.033
UTI in pregnancy	2 (0.9%)	188 (0.5%)	1.93a	0.48, 7.79	0.36
Hypertensionc	14 (6.5%)	1369 (3.6%)	1.79a	0.98, 3.25	0.058
Male sex	123 (57.2%)	19,681 (51.6%)	1.25a	0.96, 1.64	0.09
Birthweight (g) – mean (SD)	3036 (893)	3320 (607)	−290b	−413, −166	< 0.001
High birthweight > 4000 g	17 (7.9%)	3763 (9.9%)	0.77a	0.46, 1.31	0.34
Low birthweight < 2500 g	48 (22.3%)	2576 (6.7%)	4.03a	2.90, 5.60	< 0.001
Very low birthweight < 1500 g	21 (9.8%)	701 (1.8%)	5.81a	3.67, 9.16	< 0.001
Gestational age (weeks) – mean (SD)	37.3 (3.9)	38.8 (2.3)	−1.6b	−2.1, − 1.1	< 0.001
Preterm < 37 weeks	50 (23.3%)	3002 (7.9%)	3.58a	2.58, 4.95	< 0.001
Birthweight z-score – mean (SD)	−0.04 (1.14)	− 0.06 (0.93)	0.03b	− 0.13, 0.19	0.72

Data are n (%), unless otherwise specified. Denominators added if missing data

^aodds ratio; ^bmean difference; ^cessential or pregnancy-induced

CI Confidence Interval, BMI Body Mass Index, APH Antepartum Haemorrhage, HELLP Haemolysis, Elevated Liver enzymes and low Platelet levels