AIM: The aim of this study is to compare the prevalence of bacterial vaginosis in patients having preterm rupture of membranes or preterm labour with the prevalence of bacterial vaginosis in patient with term pregnancy. METHOD: A cross-sectional case control study. The case group consists of 44 pregnant women at 28-36 weeks and 6 days with preterm rupture of membranes and or preterm labour while the control group consists of 48 women above 37 weeks with or without rupture of membranes. The two groups were screened for bacterial vaginosis using the Nugent method. Nugent score of 7 and above was considered as positive for bacterial vaginosis