Prevalence of asymptomatic bacteriuria among pregnant women in Shiraz, Iran

OBJECTIVE: To determine the frequency of asymptomatic bacteriuria in pregnant women referred to a University College Hospital in Shiraz, Iran for perinatal care, and also to determine the relation between asymptomatic bacteriuria and pyuria.

METHODS: This cross-sectional case series study included 389 healthy pregnant women who were referred to Hafez Hospital, Shiraz, Iran, antenatal care unit for regular perinatal care between May and August 2007. A specimen from each candidate was collected and processed following the standard microbiological technique. All the subjects were evaluated for bacteriuria.

RESULTS: The mean age of the patients was 26.3 +/= 4.2 years. The prevalence of asymptomatic bacteriuria was 5.1%. From 75 (19.2%) patients who had >/- 5 pus cells in high power field, only 12 (16%) had positive urine culture. The most common isolated microorganism was Escherichia coli (70%) followed by Staphylococcus aureus (20%) and Group B Streptococcus (5%).

CONCLUSION: We found a rate of bacteriuria in our cohort of asymptomatic pregnant subject that is well within the reported range from the literature. A negative test for pyuria is not a reliable indicator of the absence of asymptomatic bacteriuria in pregnant women. To prevent asymptomatic bacteriuria complications, all pregnant women should be screened at the first antenatal visit.