This case-control study was done to identify the correlation between the familial, social and environmental risk factors and autism. This hospital and specialized centre based study done from January 2002 to November, 2004. Thirty two children from the autism group and 14 children from the control group were enrolled. Mean age were 3.75 yrs. and 2.83 yrs. respectively. Significant proportion of children were in the highest birth orders, 68.8% in autism and 78.6% in the control group. Full term children were 96.9% and 92.9% respectively. 53.1% children in the autism and 57.1% in the normal speech delay group were born by cesarean sections.