Background: The prevalence of obesity or overweight in pregnancy is also rising and is of international concern. The aim of the study was to evaluate and compare the maternal and perinatal outcome in patients with BMI 20-24.9 kg/m2 (normal), with BMI 25-29.9 kg/m2 (overweight) and with BMI >30 kg/m2 (obese). Methods: This cross-sectional study was conducted on 150 singleton pregnant women with gestational age>37 weeks with cephalic presentation. The selected women were categorized into three groups of 100 each according to their BMI: Category I included normal women (BMI 20-24.9 kg/m2), Category II included overweight women (BMI 25- 29.9 kg/m2) and Category III included obese women (BMI >30 kg/m2). Results: In Category I mean age of normal women was 28.5 ± 4 years, in Category II, mean age of overweight women was 29.5± 4 years; and in Category III, mean age of obese women was 31.5± 6 years. The mean weight of Category I (56.72 kg), Category II (65.77 kg) and Category III (80.71 kg). There was increased incidence of antepartum complications in Category III women as compared to Category II and Category I women. Under perinatal complications, 10% babies born to women in Category III needed NICU admission as compared to 5% in Category II and 2% in Category I. The difference in the incidence of NICU admissions was statistically significant. Conclusion: This study concluded that increase in BMI lead to increased Incidence of Pre-eclampsia, GDM, Post term pregnancy, Caesarean section rate with no increase Incidence in post-partum haemorrhage. As perinatal complications increase in BMI lead to increased Incidence of Macrosomia and NICU admission with no increase Incidence of still birth rate.