Parental occupation, Hispanic ethnicity, and risk of selected congenital malformations in offspring

Evidence suggests that parental occupation and Hispanic ethnicity may be risk factors for some birth defects. Because few studies have examined the effect of Hispanic ethnicity on occupational associations, we examined whether risk associated with certain occupations was heightened in Hispanics compared with non-Hispanic Whites.

In this case-control study among Texas births occurring from 1996 through 2000, cases of neural tube defects, isolated oral clefts, and chromosomal anomalies were linked to their respective live birth certificates. A random sample of 4965 live births without documented congenital malformations served as the comparison group. Parental occupations were categorized into groups according to previously published associations. Logistic regression was used to obtain odds ratios (OR) and 95% confidence intervals (CI) for the selected congenital malformations in relation to parental occupations.

Maternal occupations as cook or nurse were associated with oral clefts (OR 3.3, 95% CI .6-16.0) and neural tube defects (OR 3.1, 95% CI .5-13.1), respectively, among births to Hispanic mothers, but not with births to non-Hispanic White mothers. Hispanic fathers who were electricians were more likely to have offspring with chromosomal anomalies, especially trisomy 18 (OR 7.4, 95% CI 1.6-25.5), associations not seen among offspring of non-Hispanic White fathers. Risk estimates also differed by Hispanic ethnicity between oral clefts and paternal occupations of electronic equipment operator, farmworker, janitor, police officer, and printer.

In this study, we found differences for risk of several congenital malformations by Hispanic ethnicity in relation to parental occupation. We recommend further study of these risks in other Hispanic populations.