A prospective case controlled study was conducted to determine the incidence of asymptomatic bacteriuria in pregnancy (ASB), causative organisms and fetal outcome. Out of 510 antenatal mothers screened, 46 (9%) had ASB. The main organisms isolated were E. coli (16%), Staphylococcus aureus (15%) and Beta-Haemolytic Streptococcus (11%). Oral Nitrofurantoin and Cefuroxime axetil achieved sensitivity levels of 96%. There was no significant difference in period of gestation at birth and birthweight between the control and study groups. The reasons for routine antimicrobial therapy for ASB are discussed.