The present study was conducted to learn whether the perinatal and environmental factors could influence the total and antigen-specific IgE levels in umbilical cord blood. Retrospective data were obtained from 173 mother-infant pairs. Total and specific (for children's food, wheat/grass and house dust mite-HDM) cord blood IgE levels were determined using the immunoassay test. The total cord blood IgE was between 0.0-23.08 IU/ml (mean 0.55 +/-2.07 IU/ml; median 0.16 IU/ml). Total IgE levels were significantly higher in boys compared with girls (OR=2.2; P=0.007), and in newborns with complicated pregnancy (OR=2.7; P=0.003). A greater number of siblings correlated with increases in the total cord blood IgE (P<0.02). We detected specific IgE in 34 newborns (40 positive tests). A long-standing contact with a cat during pregnancy decreased the specific IgE level for wheat/grass (OR=3.2; P<0.07) and for children's food (OR=5.0; P<0.04), and the contact with a dog decreased the specific-IgE for wheat/grass (OR=0.3; P<0.05). Exposure to tobacco smoke correlated with the positive specific IgE toward house dust mite (OR=4.7; P=0.005).