Environmental factors and risk of orofacial clefts in the democratic republic of congo

Orofacial clefts are among the most common birth defects in the world. Etiology of cleft lips and palates has not been extensively studied and are primarily based in higher income countries and the Caucasian population. The University of Southern California in partnership with Operation Smile is investigating genetic and environmental factors in the etiology of clefts. Cases defined as children with clefts were enrolled during an Operation Smile surgical mission in Kinshasa, the Democratic Republic of Congo (DRC) along with their biological parents. Controls defined as non-cleft newborns and their biological parents were recruited from local maternity wards. Self-reported questionnaires were administered by local translators to mothers containing questions about environmental factors, prenatal behaviors and lifestyle factors. Multivariate logistic regression analysis shows an increased risk of orofacial cleft was associated with living in a rural area during pregnancy (p=0.0004; OR 16.6; 95% CI 1.86-148.1) and marginally associated with living on a farm during pregnancy (p=0.081; OR 7.6; 95% CI 0.78-74.1). A decreased risk of orofacial cleft was associated with consuming public water during pregnancy (p=0.006; OR 0.37; 95% CI 0.18-0.75). These findings suggest that women in rural areas and environmental exposures may contribute to the etiology of this congenital abnormality. The protective nature of public drinking water reveals an area that should be considered in future studies and analyzed further. With additional studies on maternal exposures in DRC, preventive measures may be implemented to reduce the incidence of orofacial clefts.