Table 4

Adjusted odds ratios and 95% confidence intervals for the association between occupational groups and birth defect systems among the children of mothers with jobs during the critical period who participated in the National Birth Defects Prevention Study, 1997–2003*

Occupational groupAmniotic bandCentral nervous systemEarEyeGastrointestinal
nOR (95% CI)nOR (95% CI)nOR (95% CI)nOR (95% CI)nOR (95% CI)
Computer scientists080.69 (0.32 to 1.47)20.58 (0.13 to 2.58)21.23 (0.42 to 3.59)130.96 (0.53 to 1.76)
Scientists20.93 (0.22 to 4.03)141.37 (0.79 to 2.39)20.84 (0.20 to 3.57)20.63 (0.19 to 2.06)181.30 (0.76 to 2.24)
Artists12.44 (0.31 to 19.29)62.45 (0.97 to 6.16)12.48 (0.51 to 12.03)01.88 (0.22 to 15.86)41.12 (0.36 to 3.46)
Healthcare workers90.87 (0.44 to 1.71)1041.20 (0.96 to 1.51)170.95 (0.57 to 1.58)231.17 (0.76 to 1.81)1061.13 (0.90 to 1.42)
Public servants051.26 (0.56 to 2.86)32.57 (0.74 to 8.89)23.32 (1.06 to 10.40)71.26 (0.56 to 2.82)
Food servers/processors141.39 (0.79 to 2.46)1031.18 (0.93 to 1.49)160.78 (0.47 to 1.30)150.84 (0.50 to 1.39)740.83 (0.64 to 1.08)
Janitors/cleaners62.41 (1.04 to 5.59)351.49 (1.02 to 2.19)122.67 (1.47 to 4.85)113.27 (1.78 to 5.99)311.48 (0.99 to 2.20)
Personal service/athletes71.84 (0.88 to 3.83)351.07 (0.75 to 1.52)50.70 (0.28 to 1.75)70.93 (0.46 to 1.92)301.05 (0.73 to 1.51)
Hairdressers10.57 (0.07 to 4.48)81.06 (0.54 to 2.08)42.24 (0.77 to 6.51)0100.97 (0.48 to 1.95)
Office, other†121.25 (0.64 to 2.43)630.96 (0.72 to 1.27)50.31 (0.12 to 0.77)201.29 (0.80 to 2.07)831.11 (0.86 to 1.44)
Managers10.39 (0.12 to 1.26)490.91 (0.67 to 1.24)181.75 (1.03 to 2.96)180.83 (0.48 to 1.44)670.97 (0.74 to 1.29)
Teachers60.70 (0.30 to 1.64)460.67 (0.49 to 0.92)141.04 (0.58 to 1.88)160.73 (0.42 to 1.25)630.88 (0.67 to 1.16)
Sales workers101.00 (0.56 to 1.77)881.03 (0.82 to 1.29)201.29 (0.84 to 1.99)181.01 (0.64 to 1.59)830.96 (0.76 to 1.22)
Administrative support231.22 (0.76 to 1.97)1470.97 (0.80 to 1.17)270.76 (0.50 to 1.17)290.86 (0.58 to 1.27)1571.00 (0.82 to 1.21)
Farm workers21.22 (0.26 to 5.77)271.43 (0.86 to 2.36)72.03 (0.84 to 4.91)31.11 (0.31 to 4.02)121.01 (0.55 to 1.88)
Landscapers001.11 (0.11 to 10.84)216.12 (0.73 to 50.94)35.23 (1.14 to 23.86)
Construction workers11.15 (0.15 to 8.84)60.99 (0.47 to 2.10)10.51 (0.07 to 3.93)21.11 (0.24 to 5.04)50.73 (0.30 to 1.77)
Metal workers/welders222.05 (3.66 to 132.73)31.87 (0.44 to 8.04)0033.22 (0.90 to 11.48)
Dry cleaners020.68 (0.15 to 3.19)10.84 (0.10 to 7.09)01.14 (0.13 to 9.92)31.65 (0.54 to 5.00)
Chemical/semiconductor workers12.28 (0.28 to 18.37)51.86 (0.78 to 4.43)31.88 (0.50 to 7.10)22.27 (0.60 to 8.60)61.56 (0.62 to 3.89)
Textile/paper workers050.65 (0.27 to 1.61)10.46 (0.06 to 3.51)20.97 (0.22 to 4.34)40.78 (0.32 to 1.91)
Shippers, operators10.50 (0.07 to 3.76)110.68 (0.38 to 1.22)61.09 (0.45 to 2.65)30.69 (0.24 to 1.97)221.17 (0.72 to 1.90)
Electronic equipment operators12.20 (0.62 to 7.72)131.87 (1.04 to 3.36)10.93 (0.21 to 4.14)20.88 (0.19 to 3.97)60.65 (0.27 to 1.57)
Manufacturing/transportation workers0100.92 (0.47 to 1.81)53.03 (1.19 to 7.70)20.86 (0.20 to 3.72)121.14 (0.59 to 2.20)
Occupational groupGenitourinaryCardiovascularMusculoskeletalOrofacial
nOR (95% CI)nOR (95% CI)nOR (95% CI)nOR (95% CI)
Computer scientists251.26 (0.69 to 2.29)491.00 (0.68 to 1.47)251.12 (0.70 to 1.81)291.28 (0.82 to 2.00)
Scientists151.56 (0.76 to 3.21)561.13 (0.78 to 1.63)241.01 (0.63 to 1.61)200.93 (0.56 to 1.55)
Artists30.54 (0.13 to 2.24)151.27 (0.61 to 2.64)50.99 (0.39 to 2.49)81.58 (0.66 to 3.76)
Healthcare workers880.89 (0.67 to 1.18)3390.88 (0.75 to 1.02)1781.03 (0.85 to 1.24)1400.82 (0.67 to 1.00)
Public servants71.42 (0.54 to 3.77)170.78 (0.42 to 1.45)90.92 (0.44 to 1.94)70.84 (0.39 to 1.81)
Food servers/processors490.81 (0.57 to 1.14)2910.95 (0.80 to 1.12)1871.06 (0.88 to 1.29)1620.96 (0.78 to 1.17)
Janitors/cleaners100.56 (0.28 to 1.11)841.16 (0.87 to 1.54)401.19 (0.85 to 1.67)481.40 (0.99 to 1.98)
Personal service/athletes260.91 (0.58 to 1.44)1070.89 (0.70 to 1.13)591.07 (0.80 to 1.42)540.98 (0.73 to 1.32)
Hairdressers121.33 (0.63 to 2.84)391.12 (0.74 to 1.72)231.15 (0.69 to 1.92)241.49 (0.90 to 2.45)
Office, other†1101.20 (0.91 to 1.59)2850.98 (0.82 to 1.15)1441.05 (0.85 to 1.29)1551.22 (0.99 to 1.50)
Managers830.93 (0.68 to 1.26)2531.00 (0.84 to 1.20)830.67 (0.52 to 0.87)930.79 (0.62 to 1.01)
Teachers640.81 (0.59 to 1.13)2220.82 (0.68 to 0.98)980.80 (0.64 to 1.01)970.81 (0.64 to 1.03)
Sales workers781.24 (0.92 to 1.66)3541.09 (0.94 to 1.27)1790.97 (0.81 to 1.17)1370.86 (0.70 to 1.04)
Administrative support1490.97 (0.77 to 1.23)6181.01 (0.89 to 1.14)3451.22 (1.05 to 1.41)2931.12 (0.96 to 1.30)
Farm workers51.28 (0.49 to 3.38)421.14 (0.75 to 1.73)281.01 (0.62 to 1.62)271.21 (0.75 to 1.95)
Landscapers081.71 (0.41 to 7.18)10.51 (0.05 to 5.08)10.80 (0.08 to 7.75)
Construction workers81.26 (0.52 to 3.08)301.01 (0.61 to 1.67)130.94 (0.50 to 1.75)201.34 (0.77 to 2.35)
Metal workers/welders091.74 (0.59 to 5.18)31.17 (0.27 to 4.96)42.31 (0.66 to 8.13)
Dry cleaners46.90 (0.75 to 63.63)141.79 (0.80 to 3.97)51.10 (0.37 to 3.28)71.77 (0.71 to 4.44)
Chemical/semiconductor workers41.26 (0.38 to 4.20)241.73 (0.92 to 3.27)101.15 (0.50 to 2.68)71.55 (0.70 to 3.41)
Textile/paper workers00.12 (0.01 to 1.13)280.97 (0.57 to 1.66)111.03 (0.53 to 2.02)161.29 (0.69 to 2.42)
Shippers, operators90.68 (0.32 to 1.44)570.88 (0.62 to 1.24)250.78 (0.50 to 1.23)250.86 (0.55 to 1.33)
Electronic equipment operators20.45 (0.12 to 1.69)271.08 (0.67 to 1.73)161.21 (0.69 to 2.10)151.20 (0.67 to 2.13)
Manufacturing/transportation workers70.81 (0.34 to 1.94)330.95 (0.61 to 1.48)151.01 (0.59 to 1.72)201.12 (0.64 to 1.94)
  • *Models are adjusted for the following: study centre, folic acid use, maternal age at delivery, maternal pre-pregnancy body mass index, maternal race/ethnicity, maternal education, parity, maternal smoking and maternal alcohol use during the first trimester. The critical period is defined as 1 month prior to conception through the end of the third month of pregnancy. Some infants may be represented in the table more than once if they have multiple defects.

  • †Includes business/financial specialists, architects/drafters/designers, legal/social workers, media/communication workers and messengers.