PARENTAL OCCUPATION,HISPANIC ETHNICITY, AND RISK OF SELECTED CONGENITAL MALFORMATIONS IN OFFSPRING Jean D. Brender, PhD, RN; Lucina Suarez, PhD; Peter H. Langlois, PhD Objectives: 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. Design: 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 re- gression was used to obtain odds ratios (OR) and 95% confidence intervals (CI) for the selected congenital malformations in relation to parental occupations. Results: 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 elec- tronic equipment operator, farmworker, jani- tor, police officer, and printer. Conclusions: In this study, we found differ- ences for risk of several congenital malforma- tions by Hispanic ethnicity in relation to parental occupation. We recommend further study of these risks in other Hispanic popula- tions. (Ethn Dis. 2008;18:218–224) Key Words: Birth Defects, Occupational Groups, Hispanic, Ethnicity INTRODUCTION Congenital malformations remain the greatest contributor to infant mor- tality. 1 In the United States, the prev- alence of several birth defects varies by maternal ethnicity, such as neural tube defects (NTDs: anencephalus, spina bifida, encephalocele), oral clefts (cleft lip with or without cleft palate, cleft palate alone), and chromosomal anom- alies. Compared with births to non- Hispanic White mothers, more children born to Hispanic White mothers have neural tube defects 2,3 and Down syn- drome. 3 On the other hand, the prevalence of cleft palate is lower among Hispanic births than among non-His- panic White births. 3–5 Differences in genetic background, nutrition and use of supplements, socioeconomic status, use of prenatal diagnostic technologies, and environmental or occupational exposures might account for the ethnic differential in prevalence of these de- fects. During the past 20 years, several studies have been published regarding the relationship between maternal and paternal occupation and various types of congenital malformations. Positive associations have been noted between parental occupation and offspring with NTDs, 6–11 oral clefts, 9,12 and chromo- somal anomalies, 13 including Down syndrome. 14 Although several studies have been conducted in the United States regard- ing the relationship between parental occupation and risk of congenital mal- formations in offspring, few have spe- cifically addressed the potential differ- ences in these risks by Hispanic ethnicity. In this study, we examined whether Hispanic ethnicity modified any associations between parental occu- pations (based on job titles and expo- sures found associated with these defects in other studies) and risk for NTDs, oral cleft defects, and chromosomal anomalies. METHODS Study Population Case and control births were select- ed from births to Texas residents from 1996 through 2000. The Texas Birth Defects Registry (TBDR) conducts active birth defect surveillance by re- viewing medical facility log books, hospital discharge lists, and other rec- ords. Although the TBDR includes spontaneous abortions, fetal deaths, and elective terminations with eligible defects in the surveillance system, we Address correspondence and reprint requests to: Jean D. Brender, PhD; Associate Professor; Department of Epidemiology and Biostatistics; Texas A&M Health Science Center, School of Rural Public Health; 201 SRPH Administration Building; College Sta- tion, TX 77843-1266; 979-862-1573; 979- 458-1877 (fax); jdbrender@srph.tamhsc.edu From the Department of Epidemiology and Biostatistics, Texas A&M Health Sci- ence Center, School of Rural Public Health, College Station (JDB); Epidemiology and Disease Surveillance Unit (LS), Birth Defects Epidemiology and Surveillance Branch (PHL), Texas Department of State Health Services, Austin, Texas, USA. We examined whether Hispanic ethnicity modified any associations between parental occupations … and risk for NTDs, oral cleft defects, and chromosomal anomalies. 218 Ethnicity & Disease, Volume 18, Spring 2008