Urinary tract infections during pregnancy

OBJECTIVE: To provide a comprehensive review of urinary tract infections (UTIs) during pregnancy. All aspects of UTIs, including epidemiology, pathogenesis, resistance, clinical features, diagnosis, treatment, and prevention, were reviewed. DATA SOURCES: MEDLINE (1966-August 2003) and Cochrane Library searches were performed using the key search terms urinary tract infection, pyelonephritis, cystitis, asymptomatic bacteriuria, and resistance. STUDY SELECTION AND DATA EXTRACTION: All article abstracts were evaluated for relevance. Only articles pertaining to pregnancy were included. The majority of published literature were review articles; the number of original clinical studies was limited. DATA SYNTHESIS: UTIs are the most common bacterial infections during pregnancy. They are characterized by the presence of significant bacteria anywhere along the urinary tract. Pyelonephritis is the most common severe bacterial infection that can lead to perinatal and maternal complications including premature delivery, infants with low birth weight, fetal mortality, preeclampsia, pregnancy-induced hypertension, anemia, thrombocytopenia, and transient renal insufficiency. Enterobacteriaceae account for 90% of UTIs. The common antibiotics used are nitrofurantoin, cefazolin, cephalexin, ceftriaxone, and gentamicin. CONCLUSIONS: Therapeutic management of UTIs in pregnancy requires proper diagnostic workup and thorough understanding of antimicrobial agents to optimize maternal outcome, ensure safety to the fetus, and prevent complications that lead to significant morbidity and mortality in both the fetus and the mother.