Background: Asymptomatic bacteriuria has been demonstrated to have adverse maternal and pregnancy outcomes precisely pyelonephritis, low birth weight, preterm premature rupture of membranes and preterm labour.

Objective: This study aimed to determine the prevalence of asymptomatic bacteriuria and antibiotic sensitivity pattern among women attending antenatal clinic at Kilimanjaro Christian Medical Centre in Northern Tanzania.

Methodology: We conducted analytical cross sectional study involving women attending antenatal clinic at Kilimanjaro Christian Medical Centre between October and December 2016. All women who met the inclusion criteria and gave their informed consent were invited to participate. Interviews using a questionnaire were conducted to collect socio-demographic and obstetric information while urine samples were collected for laboratory processing.

Results: The prevalence of asymptomatic bacteriuria (ASB) among pregnant women in this study was 8.9%. The organisms isolated from the urine sample according to the frequency of occurrence were Escherichia coli (50%), Streptococcus pyogenes (19%), Klebsiella pneumoniae (15%), group B Streptococcus (8%), group A Streptococcus (4%) and Proteus mirabilis (4%). The rate of antibiotic sensitivity among gram negative bacteria ranged from 100% among Escherichia coli and Proteus mirabilis to ceftriaxone, while Klebsiella pneumoniae and Proteus mirabilis showed no sensitivity at all to ampicillin. Among the gram positive bacteria, erythromycin was shown to have sensitivity to group A streptococcus but no sensitivity to group B streptococcus.

Conclusion: The prevalence of asymptomatic bacteriuria of 8.9% among pregnant women and the wide array of organisms isolated in this population warrant the development of protocols for routine ASB screening and exclusion of ampicillin as an antibiotic of choice in this cohort.