The etiology and prevalence of urinary tract infection and asymptomatic bacteriuria in pregnant women in Iran: a systematic review and Meta-analysis

Background: Urinary tract infection (UTI) is a common clinical problem in pregnant women. Bacteriuria in pregnancy without antibiotic treatment could result in complications. This study aims to investigate the etiology and prevalence of UTI and asymptomatic bacteriuria (ASB) in pregnant women in Iran. Method: This meta-analysis followsthe Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. To avoid bias, all steps of the study were carried out independently by two researchers. We conducted a comprehensive search on all the related literature in national databases, including IranDoc, SID, Barakat Knowledge Network System, RICST, Magiran, Iranian National Library and international databases, including Scopus, Embase, Science Direct, PubMed/ Medline, Cochrane Library, Web of Sciences, EBSCO, as well as Google Scholar search engine until June 2018. After considering the inclusion/exclusion criteria and qualitative evaluation, studies were analyzed based on random effects model using Comprehensive Meta-Analysis Software Version 2. Results: In 31 studies with a sample size of 20,309, the prevalence of ASB in pregnant Iranian women was estimated to be 8.7% (95%CI: 7.2-10.4). The lowest and highest prevalence of ASB were observed in the third trimester (6.1% [95%CI: 2.1-16.4]) and first trimester (11.7% [95%CI: 7.9-16.9]), respectively. Subgroup analysis of the prevalence of ASB based on geographical region (P=0.002) and province (P<0.001) was significant but for the quality of studies (P=0.51) was not significant. In 17 studies including 48,731 pregnant women, the prevalence of UTI was estimated to be 9.8% (95%CI: 7.6-12.5). The test for subgroup differences of prevalence of UTI for province (P<0.001) was significant but for geographical region (P=061) and quality of studies (P=0.11) was not significant. Meta-regression model for the prevalence of UTI and ASBin pregnant women in Iran based on year of the studies was significant (P<0.001). The most common microorganism involved in the etiology ofUTI (61.6% [95%CI: 51.6-70.7]) and ASB (63.22% [95%CI: 51.2-73.8]) was E. coli. Conclusion: UTI and ASB are prevalent in pregnant women in Iran. Therefore, UTI screening is essential in pregnant women. The most common microorganism involved in the etiology of UTIand ASB in pregnant women in Iran is E.coli.