| | |
National
|
Caseload practices
|
Matched controls
|
p-value (caseload vs matched)
|
|---|
|
n = 127,818
|
n = 657
|
n = 1954
|
|---|
|
Maternal age
| | | | | | | |
na
|
a
|
| |
Mean
|
30.4
|
(SD 4.6)
|
31.6
|
(SD 4.5)
|
31.4
|
(SD 4.4)
| | |
| |
< 25
|
13,197
|
(10.3%)
|
32
|
(4.9%)
|
99
|
(5.1%)
| | |
| |
25–29
|
41,138
|
(32.2%)
|
192
|
(29.2%)
|
567
|
(29.0%)
| | |
| |
30–34
|
49,438
|
(38.7%)
|
272
|
(41.4%)
|
814
|
(41.7%)
| | |
| |
35–39
|
20,885
|
(16.3%)
|
132
|
(20.1%)
|
393
|
(20.1%)
| | |
| |
≥40
|
3160
|
(2.5%)
|
29
|
(4.4%)
|
81
|
(4.1%)
| | |
|
Parity
| | | | | | | |
na
|
a
|
|
(missing: 2)
|
0
|
58,608
|
(45.8%)
|
319
|
(48.6%)
|
940
|
(48.1%)
| | |
| |
1
|
46,010
|
(36.0%)
|
240
|
(36.5%)
|
722
|
(36.9%)
| | |
| |
≥2
|
23,198
|
(18.1%)
|
98
|
(14.9%)
|
292
|
(14.9%)
| | |
|
Background
| | | | | | | |
na
|
a
|
| |
Dutch
|
96,589
|
(75.6%)
|
522
|
(79.5%)
|
1555
|
(79.6%)
| | |
| |
Non Dutch
|
31,229
|
(24.4%)
|
135
|
(20.5%)
|
399
|
(20.4%)
| | |
|
SES
| | | | | | | |
0.019
|
b
|
|
(missing 574)
|
1 (low)
|
41,146
|
(32.3%)
|
237
|
(36.7%)
|
757
|
(39.0%)
| | |
| |
2 (intermediate)
|
55,949
|
(44.0%)
|
248
|
(38.4%)
|
802
|
(41.4%)
| | |
| |
3 (high)
|
30,149
|
(23.7%)
|
160
|
(24.8%)
|
380
|
(19.6%)
| | |
|
Urbanisation
| | | | | | | |
< 0.001
|
b
|
|
(missing 206)
|
Very urban
|
31,693
|
(24.8%)
|
184
|
(28.1%)
|
539
|
(27.6%)
| | |
| |
Urban
|
32,707
|
(25.6%)
|
193
|
(29.5%)
|
360
|
(18.4%)
| | |
| |
Semi-urban
|
23,989
|
(18.8%)
|
65
|
(9.9%)
|
253
|
(13.0%)
| | |
| |
Rural
|
21,991
|
(17.2%)
|
93
|
(14.2%)
|
467
|
(23.9%)
| | |
| |
Very Rural
|
17,232
|
(13.5%)
|
119
|
(18.2%)
|
333
|
(17.1%)
| | |
|
Gestational age at intake in practice
| | | | | | |
< 0.001
|
b
|
|
(missing 1206)
|
≤12
|
112,767
|
(89.1%)
|
480
|
(73.2%)
|
1770
|
(90.6%)
| | |
| |
13–27
|
10,578
|
(8.4%)
|
101
|
(15.4%)
|
131
|
(6.7%)
| | |
| |
28–36
|
2763
|
(2.2%)
|
57
|
(8.7%)
|
37
|
(1.9%)
| | |
| |
≥37 wk
|
506
|
(0.4%)
|
18
|
(2.7%)
|
3
|
(0.2%)
| | |
|
Antenatally planned place of birth
| | | | | | |
< 0.001
|
b
|
|
(missing 3269)
|
home
|
27,111
|
(21.8%)
|
291
|
(44.5%)
|
387
|
(20.3%)
| | |
| |
birthcentre
|
12,666
|
(10.2%)
|
28
|
(4.3%)
|
87
|
(4.6%)
| | |
| |
hospital
|
70,322
|
(56.5%)
|
272
|
(41.6%)
|
1177
|
(61.6%)
| | |
| |
undecided
|
14,450
|
(11.6%)
|
63
|
(9.6%)
|
259
|
(13.6%)
| | |
|
Gestational age at birth in weeks
| | | | | | |
< 0.001
|
b
|
|
(missing 1432)
|
< 370
|
5121
|
(4.1%)
|
20
|
(3.1%)
|
80
|
(4.1%)
| | |
| |
37–416
|
119,429
|
(94.5%)
|
601
|
(91.8%)
|
1829
|
(94.2%)
| | |
| |
≥420
|
1836
|
(1.5%)
|
34
|
(5.2%)
|
32
|
(1.6%)
| | |
| |
Mean
|
39.3
|
(SD 1.5)
|
39.5
|
(SD 1.6)
|
39.3
|
(SD 1.5)
|
0.004
|
c
|
|
Birthweight (gram)
| | | | | | | | | |
|
(missing 796)
|
Mean
|
3469
|
(SD 513)
|
3.495
|
(SD 499)
|
3.475
|
(SD 508)
|
0.382
|
c
|
| |
SGA (<p5)
|
4575
|
(3.6%)
|
26
|
(4.0%)
|
61
|
(3.1%)
|
0.302
|
b
|
| |
LGA (>p95)
|
5765
|
(4.5%)
|
26
|
(4.0%)
|
82
|
(4.2%)
|
0.790
|
b
|
|
Birthweight Categories
| | | | | | |
0.424
|
b
|
| |
< 2500
|
4267
|
(3.3%)
|
12
|
(1.8%)
|
52
|
(2.7%)
| | |
| |
2500–4500
|
120,844
|
(94.7%)
|
630
|
(96.0%)
|
1863
|
(95.3%)
| | |
| |
> 4500
|
2459
|
(1.9%)
|
14
|
(2.1%)
|
35
|
(1.8%)
| | |
|
Multiple pregnancy
| |
135
|
(0.1%)
|
1
|
(0.2%)
|
3
|
(0.2%)
| | |
|
Non-vertex presentation at birth
|
breech
|
3881
|
(3.0%)
|
15
|
(2.3%)
|
58
|
(3.0%)
| | |
| |
other / unknown
|
2746
|
(2.1%)
|
8
|
(1.2%)
|
42
|
(2.1%)
| | |
- anot applicable, matching variable
- bChi Square
- cTwo-sided t-test
