BACKGROUND: Traditional farming represents a unique model situation to investigate the relationship of early-life farm-related exposure and allergy protection. OBJECTIVES: To investigate associations between maternal farm exposures and cytokine production in cord blood (CB) mononuclear cells in a prospective multinational birth cohort of 299 farm and 326 nonfarm children and their families. METHODS: Supernatants from phorbol 12-myristate 13-acetate/ionomycin-stimulated CB mononuclear cells were assessed for the production of IFN-gamma, TNF-alpha, IL-5, IL-10, and IL-12. RESULTS: Significantly higher levels of IFN-gamma and TNF-alpha in farm compared with nonfarm children were found, whereas IL-5, IL-10, and IL-12 levels did not differ between study groups. Maternal contact with different farm animal species and barns and consumption of farm-produced butter during pregnancy enhanced the production of proinflammatory CB cytokines, whereas maternal consumption of farm-produced yogurt resulted in significant lower levels of IFN-gamma and TNF-alpha in umbilical blood. CONCLUSION: Maternal exposure to farming activities and farm dairy products during pregnancy modulated cytokine production patterns of offspring at birth