Table 3

Odds ratios of total and selected birth defects by paternal occupational exposure to magnetic fields above 0.1 μT in Norway 1967–95

CrudeAdjusted†
Category of birth defectsHours exposed/weekCases (n)OR95% CIp Value*OR95% CIp Value*
*Test for trend across three exposure categories; †adjusted for highest family educational level, place of birth, mothers' age, and year of birth; ‡refers to the ICD-8 category 758.
Any birth defect<4289371.000.00021.000.11
4–2428310.970.93 to 1.011.030.99 to 1.07
>2410880.900.84 to 0.951.030.97 to 1.09
All CNS defects<414301.000.061.000.22
4–241681.160.99 to 1.371.130.96 to 1.32
>24681.130.89 to 1.451.070.84 to 1.37
Anencephaly<43471.000.00041.000.01
4–24571.631.23 to 2.151.521.15 to 2.02
>24231.581.04 to 2.411.390.91 to 2.13
Spina bifida<45351.000.291.000.24
4–24541.000.76 to 1.320.980.74 to 1.30
>24160.710.44 to 1.170.700.42 to 1.15
Hydrocephaly<43831.000.541.000.71
4–24370.960.68 to 1.340.940.67 to 1.32
>24201.250.79 to 1.951.190.75 to 1.86
Other CNS defects<41721.000.211.000.27
4–24211.210.77 to 1.901.170.74 to 1.84
>24101.390.73 to 2.621.350.71 to 2.57
Cardiac defects<421841.000.741.000.42
4–242281.030.90 to 1.191.090.95 to 1.25
>24840.920.74 to 1.141.010.81 to 1.26
Respiratory system defects<45651.000.011.000.50
4–24490.860.64 to 1.151.020.76 to 1.36
>24120.510.29 to 0.900.750.42 to 1.33
Isolated cleft palate<45431.000.431.000.66
4–24631.150.89 to 1.491.110.85 to 1.44
>24241.050.70 to 1.591.000.66 to 1.51
Total cleft lip<415131.000.171.000.22
4–241631.070.91 to 1.251.060.90 to 1.25
>24731.150.91 to 1.461.140.90 to 1.44
Genital system defects<442651.000.061.000.65
4–243840.890.80 to 0.990.960.87 to 1.07
>241670.930.80 to 1.091.090.93 to 1.28
Clubfoot<467701.000.000051.000.92
4–246380.930.86 to 1.011.050.96 to 1.13
>242060.730.63 to 0.830.950.83 to 1.09
Other defects‡<4831.000.031.000.02
4–24151.791.03 to 3.101.921.10 to 3.36
>2461.720.75 to 3.951.850.80 to 4.27
Down's syndrome<412051.000.441.000.52
4–241030.850.69 to 1.040.970.79 to 1.18
>24521.030.78 to 1.361.160.88 to 1.54