Table 2 Univariate analysis: perinatal factors significantly (p<0.05) associated with death for 5713 infants born after 24 weeks and before 32 weeks in 1998–9.

Perinatal characteristic	Died/total (%)	Unadjusted OR (95% CI)	p Value	Missing
Sex			<0.0001	0
Male	254/3171 (8)	1.54 (1.24 to 1.91)
Female	136/2542 (5)	1.00
GA(weeks)			<0.0001	0
31	17/1352 (1)	1.00
30	26/1080 (2)	1.94 (1.05 to 3.59)
29	31/945 (3)	2.66 (1.47 to 4.84)
28	41/770 (5)	4.41 (2.49 to 7.82)
27	63/609 (10)	9.06 (5.25 to 15.61)
26	97/548 (18)	16.88 (9.97 to 28.57)
25	115/409 (28)	30.70 (18.17 to 51.87)
Weight for GA (centile)			<0.001	0
97+	8/92 (9)	1.58 (0.75 to 3.31)
90–<97	12/297 (4)	0.70 (0.38 to 1.27)
75–<90	37/874 (4)	0.73 (0.51 to 1.05)
25–<75	168/2949 (6)	1.00
10–<25	81/900 (9)	1.64 (1.24 to 2.16)
3–<10	37/397 (9)	1.70 (1.17 to 2.47)
<3	47/204 (23)	4.96 (3.45 to 7.11)
1 min Apgar score			<0.0001	0
4–10	227/4690 (5)	1.00
<4	163/1023 (16)	3.73 (3.01 to 4.62)
Maternal ethnicity			0.008	503
Caucasian/other	301/4268 (7)	1.00
Asian	17/329 (5)	0.72 (0.44 to 1.19)
Indigenous Australian	32/257 (12)	1.88 (1.27 to 2.76)
Maori	9/119 (8)	1.08 (0.54 to 2.15)
Pacific Islander	11/237 (5)	0.64 (0.35 to 1.19)
Presentation			0.004	642
Cephalic	213/3380 (6)	1.00
Breech	129/1427 (9)	1.48 (1.18 to 1.86)
Other	18/264 (7)	1.09 (0.66 to 1.79)
Transferred after birth (outborn)				0
Yes	54/584 (9)	1.45 (1.08 to 1.96)	0.01
No	336/5129 (6)	1.00
Hypertensive disease in pregnancy
Yes	64/1254 (5)	0.68 (0.52 to 0.90)	0.006	62
No	333/4397 (7)	1.00
Fetal distress			0.02	499
Yes	92/1061 (9)	1.34 (1.05 to 1.71)
No	275/4153 (7)	1.00

GA, Gestational age.