To assess risk factors and causes for wheezing in infants.Methods: Cross-sectional study using a standardized and validated questionnaire (Estudio Internacional de Sibilancias en Lactantes, EISL, or International Study of Wheezing in Infants). Parents of infants aged 0-12 months who attended pediatric department and outpatient of zagazig university between September 2010 until january 2012 were interviewed. The association between wheezing and factors studied was made using a prevalence ratio (PR) and confidence interval of 95% (95%CI) to perform a univariate analysis..Results: two thousand parents of infants filled out the questionnaire. The risk factors were male gender (PR = 3.43; 95%CI 2.62-4.50), low birth weight(PR = 0.42; 95%CI 0,34-0.53), absence of breast feeding (PR = 1.74; 95%CI1.41-2.16)day care attendance (PR = 2.04; 95%CI 1.65-2.53)having sibling with asthma (PR = 3.10; 95%CI 2.46-3.90)any allergic disease in family (PR = 1.25; 95%CI 1.o-1.57)infection (PR = 1.39; 95%CI 1.13-1.70)asphyxia (PR = 2.18; 95%CI 1.35-3.50)and PROM (PR = 1.24; 95%CI 1.0-1.54).Also the most common causes of wheezy chest are viral infection, asthma, and F.B aspiration.Conclusions: Independent risk factors for wheezing in the first year of life are also known risks for asthma in children and adolescents. These data are useful to predict the diagnosis of asthma and to promote its prevention (whenapplicable).