Maternal occupational risk factors for oral clefts. Occupational Exposure and Congenital Malformation Working Group.
OBJECTIVE
This study investigated the role of maternal exposures at work during pregnancy in the occurrence of oral clefts.


METHODS
The occupational exposures of 851 women (100 mothers of babies with oral clefts and 751 mothers of healthy referents) who worked during the first trimester of pregnancy were studied. All the women were part of a multicenter European case-referent study conducted using 6 congenital malformation registers between 1989 and 1992. In each center, the mother's occupational history, obtained from an interview, was reviewed by industrial hygienists who were blinded to the subject's status and who assessed the presence of chemicals and the probability of exposure. Odds ratios (OR) were estimated by a multivariate analysis including maternal occupation or occupational exposures during the first trimester of pregnancy and possible confounding factors such as center of recruitment, maternal age, urbanization, socioeconomic status, and country of origin.


RESULTS
After adjustment for confounding factors, cleft palate only was significantly associated with maternal occupation in services such as hairdressing [OR 5.1, 95% confidence interval (95% CI) 1.0-26.0] and housekeeping (OR 2.8, 95% CI 1.1-7.2). The analysis suggests that the following occupational exposures are associated with orofacial clefts: aliphatic aldehydes (OR 2.1, 95% CI 0.8-5.9) and glycol ethers (OR 1.7, 95% CI 0.9-3.3) for cleft lip with or without cleft palate and lead compounds (OR 4.0, 95% CI 1.3-12.2), biocides (OR 2.5, 95% CI 1.0-6.0), antineoplastic drugs (OR 5.0, 95% CI 0.8-34.0), trichloroethylene (OR 6.7, 95% CI 0.9-49.7), and aliphatic acids (OR 6.0, 95% CI 1.5-22.8) for cleft palate only.


CONCLUSIONS
Due to the limited number of subjects, these results must be interpreted with caution. However, they point out some chemicals already known or suspected as reproductive toxins.
Lorente
C
C
Inserm U170 Unité de recherches Epidémiologiques et Statistiques sur l'Environnement et la Santé, Villejuif, France. lorente@vjf.inserm.fr
Cordier
S
S
Bergeret
A
A
De Walle
H E
HE
Goujard
J
J
Aymé
S
S
Knill-Jones
R
R
Calzolari
E
E
Bianchi
F
F
D000328:Adult; D016022:Case-Control Studies; D002972:Cleft Palate / Q000453:epidemiology* / Q000209:etiology*; D016001:Confidence Intervals; D005060:Europe / Q000453:epidemiology; D005260:Female; D015386:Hazardous Substances / Q000009:adverse effects*; D006801:Humans; D015994:Incidence; D018811:Maternal Exposure / Q000009:adverse effects*; D008875:Middle Aged; D015999:Multivariate Analysis; D016273:Occupational Exposure / Q000009:adverse effects*; D009790:Occupations / Q000145:classification* / Q000706:statistics & numerical data; D016017:Odds Ratio; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D011297:Prenatal Exposure Delayed Effects; D011336:Probability; D012042:Registries; D012307:Risk Factors; D012959:Socioeconomic Factors; D014931:Women, Working / Q000706:statistics & numerical data
D015386:Hazardous Substances