EXPOSURE TO ORGANIC-SOLVENTS DURING PREGNANCY AND ORAL CLEFTS - A CASE-CONTROL STUDY

Prior studies on the relationship between maternal exposure to organic solvents in relation to oral clefts have been inconsistent. We re-exa mined this relationship in a case-control study conducted in the Rhone -Alpes region of France during the years 1985 to 1989. For each case, we selected two controls without congenital anomalies in the same deli very unit born during the same month. We interviewed each mother withi n the first five days after delivery about previous reproductive histo ry and exposures during the first two months after conception. If the mother had an occupational activity at that time, we asked her occupat ional physician to confirm the exposures. We compared maternal exposur e to any organic solvent between 200 infants with cleft lip and/or cle ft palate and 400 controls and the estimated odds ratio was 1.62 (95% CI 1.04-2.52). Then we compared exposures to nine subgroups of solvent s. Only the odds ratio associated with halogenated aliphatic solvents (4.40, 95% CI 1.41-16.15) was significantly different from unity. Cont rol of potential confounders-sex of child, family history, maternal ep ilepsy-did not alter this odds ratio estimate.