Treatment of asymptomatic bacteriuria during pregnancy: A risk-factor-based approach

During pregnancy, there is increased risk of ascending urinary tract infection (UTI) resulting in pyelonephritis and associated preterm delivery and low birth weight. It is therefore important that pregnant women who are at high risk of pyelonephritis because of the presence of asymptomatic bacteriuria (ASB) or cystitis receive appropriate antibiotic therapy. The aim of this position paper is to propose a risk-factor-based approach for the treatment of ASB and cystitis in pregnancy to help ensure that antibiotic treatment is prescribed only when necessary, and that the benefits of antibiotic treatment outweigh potential harms for pregnant women and neonates. Rather than advocating ASB screen-and-treat for all pregnant women who have ready access to healthcare, this risk-factor-based approach involves selective screening for ASB in pregnant women with other risk factors for UTI (previous UTI, diabetes mellitus, urinary tract abnormalities, or immunosuppression) and/or a history of preterm birth. Antibiotic treatment is indicated for persistent ASB confirmed with two urine cultures during selective high-risk screening, and for all pregnant women with cystitis confirmed by urine culture, with empiric treatment considered for symptoms of dysuria and urinary frequency. Evidence suggests that such a risk-factor-based approach will prevent progression to pyelonephritis in pregnant women with ASB and cystitis while complying with the principles of antimicrobial stewardship.