Table 7 Table of regression coefficients for the relationship between exposure to NO₂ in pregnancy and birth weight [16]. Main and stratified analysis of association between pregnancy exposure to NO₂ and birth weight

Main analysis

 Entire study population

17523

-37.9 (-49.7 to -26.0)

<0.001

16273

-43.6 (-55.8 to -31.5)

<0.001

16273

-5.6 (23.6 to 12.4)

0.54

15829

-7.4 (-19.6 to 4.8)

0.24

 Women who did not change address

15191

-37.4 (-50.2 to -24.7)

<0.001

14196

-42.7 (-55.7 to -29.6)

<0.001

14196

-7.0(-26.3 to 12.3)

0.48

13818

-4.7 (17.8 yo 8.4)

0.48

 LMP based GA only

16805

-35.4 (-47.5 to -23.2)

<0.001

15618

-408 (-53.3 to -28.4)

<0.001

15618

-3.2 (-21.6 to 15.1)

0.73

15195

-5.8 (-18.3 to 6.7)

0.36

Stratified analysis

 Oslo

4669

75 (-27.7 to 42.7)

0.68

4380

-5.9 (-42.8 to 31.0)

0.75

4285

12.5 (-24.3 to 49.3)

0.51

 Akerhus

7547

10.5 (-22.8 to 43.9)

0.54

6982

8.9 (-25.4 to 43.1)

0.61

6759

29.2 (-4.8 to 63.1)

0.09

 Bergen

3866

-15.6 (-43.7 to 12.4)

0.28

3577

-4.8 (-33.0 to 23.4)

0.74

3490

19.8 (-7.7 to 47.2)

0.16

 Hordaland

1441

-37.6 (-104.6 to 29.4)

0.27

1334

-36.0 (-103.5 to 31.5)

0.30

1295

-26.7 (-92.7 to 39.2)

0.43

 Not smoking

15440

-41.3 (-53.8 to -28.8)

<0.001

15229

-43.3 (-55.8 to -30.8)

<0.001

15229

-6.6 (-25.1 to 12.0)

0.49

14835

-5.6 (-18.2 to 6.9)

0.38

 Smoking

1083

-28.3 (-80.0 to 23.3)

0.28

1044

-45.5 (-97.7 to 6.8)

0.09

1044

22.1 (-51.8 to 96.1)

0.56

994

-27.3 (-80.1 to 25.5)

0.31

 Parity 0

8304

-16.8 (-33.3 to -0.4)

0.045

7803

-17.8 (-34.7 to -10)

0.04

7803

4.3 (-20.5 to 29.0)

0.74

7594

-8.3 (25.2 to 8.5)

0.33

 Parity 1

6326

-0.6 (-20.6 to 19.4)

0.95

5858

-6.9 (-27.4 to 13.5)

0.51

5858

21.8 (-8.2 to 51.8)

0.15

5695

2.0(-18.3 to 22.4)

0.85

 Parity ≥2

2893

-26.5 (-60.3 to 7.4)

0.13

2612

-31.0 (-66.4 to 4.4)

0.09

2612

17.8 (-31.7 to 67.4)

0.48

2540

-24.8 (-59.9 to 10.4)

0.17

 Boys

8921

-30.7 (-47.5 to -13.8)

<0.001

8290

-39.6 (-57.0 to -22.2)

<0.001

<8290

-7.5 (-33.0 to 18.1)

0.57

8040

-5.4 (-22.8 to 12.1)

0.55

 Girls

8602

-45.5 (-62. 0 to -29.1)

<0.001

7983

-47.8 (-64.8 to -30.8)

<0.001

7983

-3.6 (-28.9 to 21.8)

0.78

7789

-9.4(-26.4 to 7.6)

0.28

 Education less than high school

985

-35.4 (-95.3 to 24.5)

0.25

968

-24.5 (-83.4 to 34.5)

0.42

968

-18.4 (-96 to 60.0)

0.65

905

-27.8 (-87.2 to 31.5)

0.36

 Education high school

4173

-31.9 (-58.5 to 5.3)

0.02

4098

-36.0 (-62.3 to 9.7)

0.007

4098

10.4 (27.3 to 48.1)

0.59

3948

4.8 (-21.7 to 31.3)

0.72

 Education up to 4 years of college

6474

-41.4 (-61.5 to -23.3)

<0.001

6403

-44.0 (-62.8 to -25.3)

<0.001

6403

-1.5 (-30.2 to 27.1)

092

6262

-4.9 (-23.7 to 13.9)

0.61

 Educatiom more than 4 years of college (master of professional degree)

4866

-48.2 (-69.6 to 26.9)

<0.001

4804

-50.2 (-71.4 to -29.0)

<01001

4804

-17.8 (-49.4 to 13.8)

0.27

4714

-13.3 (-34.5 to 8.0)

0.22

 Born in winter

4097

-20.2 (-46.6 to 6.2)

0.13

3797

-35.3 (-62.5 to 8.2)

0.01

3797

7.8 (-31.1 to 46.7)

0.69

3677

4.9 (-22.4 to 32.1)

0.73

 Born in winter

4097

-20.2 (-46.6 to 6.2)

0.13

3797

-35.5 (-62.5 to -8.2)

0.01

3797

7.8 (-31.1 to 46.7)

0.69

3677

4.9 (-22.4 to 32.1)

0.73

 Born in spring

4684

-60.6 (-82.2 to -39.0)

<0.001

4355

-60.2 (-82.2 to -38.3)

<0.001

4355

-46.7 ((79.5 to -13.8)

0.005

4226

-28.5(-50.6 to -6.4)

0.01

 Born in summer

4626

-35.1 (-57.4 to -12.8)

0.002

4272

-40.5 (-63.3 to -17.6)

0.001

4272

14.2 (-20.7 to 49.1)

0.43

4167

-2.7 (-25.7 to 20.3)

0.82

 Born in autumn

4116

-28.8 (-54.9 to -2.7)

0.03

3849

-31.9 (-58.6 to -5.3)

0.03

3849

16.1 (-23.0 to 55.1)

0.42

3759

5.1 (-21.4 to 31.7)

0.70