Objectives: 1.To determine correlation between maternal BMI and perinatal outcome. 2.To study relationship between BMI and maternal complications. 3.To assess relation of BMI with maternal anaemia, Methods : A study was conducted in department of obstetrics and gynaecology , J.N.M.C.H., Aligarh.during Januan- to June 2008.Around 300 pregnant females were selected who attended antenatal clinic and where diveded in groups on the basis of BMI. Results : Higher incidence of caesarean section was seen with BMI >25 (60% versus 19.4% ). It was also associated with prolonged labour, failed induction , pre-eclampsia , representation and delayed post operative ambulation.