| | |
Pregnancy in prison (ii)
|
|---|
| | |
Birth in prison
|
Birth out of prison
|
All pregnancy in prison (ii)
|
Prison controls (iii)
|
Community controls (iv)
|
|---|
| | |
n
|
%
|
n
|
%
|
n
|
%
|
n
|
%
|
P value (v)
|
n
|
%
|
P value (v)
|
|---|
|
Maternal age (years)
| | | | | | | | | | | | | |
|
Mean
| | | | |
26.5
|
27.2
| |
30.0
|
<0.001
|
|
Less than 20
|
6
|
6.1
|
11
|
5.4
|
17
|
5.6
|
108
|
8.7
|
0.0032
|
1540
|
3.9
|
<0.0001
|
|
20–24
|
34
|
34.3
|
93
|
45.8
|
127
|
42.1
|
382
|
30.9
|
6045
|
15.4
|
|
25–29
|
32
|
32.3
|
52
|
25.6
|
84
|
27.8
|
373
|
30.1
|
11472
|
29.1
|
|
30–34
|
20
|
20.2
|
34
|
16.7
|
54
|
17.9
|
252
|
20.4
|
12798
|
32.5
|
|
35 and over
|
7
|
7.1
|
13
|
6.4
|
20
|
6.6
|
119
|
9.6
|
7414
|
18.8
|
|
Parity
| | | | | | | | | | | | |
|
None
|
30
|
30.3
|
57
|
28.1
|
87
|
28.8
|
410
|
33.1
|
0.5511
|
22061
|
56.0
|
<0.0001
|
|
One
|
29
|
29.3
|
52
|
25.6
|
81
|
26.8
|
337
|
27.2
|
9764
|
24.8
|
|
Two
|
17
|
17.2
|
38
|
18.7
|
55
|
18.2
|
207
|
16.7
|
4792
|
12.2
|
|
Three
|
10
|
10.1
|
26
|
12.8
|
36
|
11.9
|
138
|
11.1
|
1705
|
4.3
|
|
Four or more
|
13
|
13.1
|
30
|
14.8
|
43
|
14.2
|
146
|
11.8
|
1006
|
2.6
|
|
Missing/not stated
|
0
|
0.0
|
0
|
0.0
|
0
|
0.0
|
0
|
0.0
| |
39
| | |
|
Parous
| |
69
|
69.7
|
146
|
71.9
|
215
|
71.2
|
828
|
66.9
|
0.1509
|
17267
|
43.9
|
<0.0001
|
|
Aboriginal/Torres Strait Islander
|
28
|
28.3
|
56
|
27.6
|
84
|
27.8
|
255
|
20.6
|
0.0068
|
863
|
2.2
|
<0.0001
|
|
Born in Australia
|
85
|
85.9
|
181
|
89.2
|
266
|
88.1
|
1091
|
88.1
|
0.9821
|
27598
|
70.1
|
<0.0001
|
|
Opioid Substitution Therapy (OST)
|
4
|
4.0
|
3
|
1.5
|
7
|
2.3
|
76
|
6.1
|
0.0034
|
30
|
0.1
|
<0.0001
|
|
Mental health admission
|
25
|
25.3
|
57
|
28.1
|
81
|
26.8
|
318
|
25.7
|
2345
|
6.0
|
|
Mental health admission and OST
|
41
|
41.4
|
108
|
53.2
|
149
|
49.3
|
510
|
41.2
|
136
|
0.3
|
|
Mental health admission or OST
|
70
|
70.7
|
168
|
82.8
|
237
|
78.5
|
904
|
73
|
0.0394
|
2511
|
6.4
|
<0.0001
|
|
Cigarettes/day (vi)
| | | | | | | | | | | | |
|
None
|
23
|
23.2
|
29
|
14.3
|
52
|
17.2
|
287
|
23.2
|
0.0802
|
33699
|
85.6
|
<0.001
|
|
1–10
|
16
|
16.2
|
49
|
24.1
|
65
|
21.5
|
311
|
25.1
|
2974
|
7.6
|
|
>10
|
46
|
46.5
|
112
|
55.2
|
158
|
52.3
|
605
|
48.9
|
2428
|
6.2
|
|
Missing/not stated
|
14
|
14.1
|
13
|
6.4
|
27
|
8.9
|
35
|
2.8
| |
266
|
0.7
| |
|
Total
|
99
|
100.0
|
203
|
100.0
|
302
|
100.0
|
1238
|
100.0
| |
39367
|
100.0
| |
|
Any smoking during pregnancy
|
76
|
76.8
|
174
|
85.7
|
250
|
82.8
|
960
|
77.5
|
0.0364
|
5813
|
14.8
|
<0.0001
|
|
Number of incarcerations (vii)
| | | | | | | | | | | | |
|
1
|
35
|
35.4
|
67
|
33.0
|
102
|
33.8
|
711
|
57.4
|
<0.0001
|
n/a
|
n/a
| |
|
2
|
14
|
14.1
|
39
|
19.2
|
53
|
17.5
|
256
|
20.7
|
n/a
|
n/a
| |
|
3
|
11
|
11.1
|
35
|
17.2
|
46
|
15.2
|
111
|
9.0
|
n/a
|
n/a
| |
|
4
|
12
|
12.1
|
15
|
7.4
|
27
|
8.9
|
67
|
5.4
|
n/a
|
n/a
| |
|
5
|
5
|
5.1
|
8
|
3.9
|
13
|
4.3
|
33
|
2.7
|
n/a
|
n/a
| |
|
6–10
|
17
|
17.2
|
32
|
15.8
|
49
|
16.2
|
55
|
4.4
|
n/a
|
n/a
| |
|
11–20
|
5
|
5.1
|
7
|
3.4
|
12
|
4.0
|
5
|
0.4
| |
n/a
|
n/a
| |
|
Total
N
| |
99
|
100.0
|
203
|
100.0
|
302
|
100.0
|
1238
|
100.0
| |
39367
|
100.0
| |
- (i) For each group, singleton births and first births during the study period (index births) only.
- (ii) Births to women who were incarcerated for a minimum of five consecutive days during this pregnancy.
- (iii) Births to women were not incarcerated during this pregnancy, but were incarcerated at another time during the study period.
- (iv) A random 10% sample of births to women who were not incarcerated at all during the study period.
- (v) One-way ANOVA and Bonferroni tests were used to test for differences between study and control groups in the distribution of maternal age; chi-square tests were used to look for differences between groups for all other maternal demographics.
- (vi) Number of cigarettes smoked per day in the second half of pregnancy (from 20 weeks gestational age onwards).
- (vii) Number of incarcerations of at least five days’ duration, 1998 to 2006.
