Table 3

 Risks of non-syndromic oral clefts associated with maternal occupational exposures to organic solvents and to non-occupational activities involving use of products containing solvents

nnOR†95% CInOR†95% CI
*Unexposed mothers are women who reported an occupational activity during the first trimester for which the expert assessed no exposure to any the three chemical classes of organic solvents (oxygenated, chlorinated, and petroleum).
†Logistic regression adjusted for centre (Rhône-Alpes, Paris, Auvergne), child’s sex, and mother’s geographic origin (Europe, other).
CL/P, cleft lip with/without cleft palate; CP, cleft palate.
n, number; OR, odds ratio; 95% CI, 95% confidence interval.
p trend = p value of the likelihood ratio test between models with and without the categorical level of exposure included as continuous variable. For each reported p trend, the test of the linearity assumption based on the comparison between the model including the exposure level as categorical and continuous variable, has not been rejected.
Maternal occupational exposure to organic solvents, among women with an occupational activity during the first trimester (187 controls, 116 CL/P, 57 CP)
Unexposed mothers* 11455ref28ref
Oxygenated solvents 71581.761.1 to 2.9281.420.7 to 2.7
Aliphatic alcohols61491.761.0 to 3.1261.560.8 to 3.0
    Very low–low39271.530.8 to 2.8131.200.5 to 2.6
    Medium–high22222.141.1 to 4.3132.201.0 to 5.1
    p trendp = 0.02p = 0.10
Glycol ethers41371.881.1 to 3.5181.500.7 to 3.2
    Very low16101.300.5 to 3.120.400.1 to 1.9
    Low22201.880.9 to 3.8121.830.8 to 4.4
    Medium–high374.771.2 to 19.544.060.8 to 20.3
    p trendp<0.01p = 0.06
Aliphatic aldehydes, esters, and ketones56461.741.0 to 2.9281.821.0 to 3.5
    Very low54421.661.0 to 2.828
    Low–medium–high244.410.7 to 26.80
    p trendp = 0.02
Chlorinated solvents 3149.452.5 to 35.333.780.7 to 20.7
Petroleum solvents 10173.641.5 to 8.831.210.3 to 4.9
    Very low–low7103.211.1 to 9.33
    Medium–high374.601.1 to 19.20
    p trendp<0.01
Extra professional activities of the mother (during the first trimester of pregnancy), among all women (236 controls, 164 CL/P, 76 CP)
Hair dyes and bleaching products
No reported use217145ref63ref
Use19171.260.6 to 2.5122.291.0 to 5.1
Painting or varnishing activities
No reported activity223151ref71ref
Yes13131.570.7 to 3.541.000.3 to 3.2