Antibiotics for asymptomatic bacteriuria in pregnancy

Area of Science:

• Obstetrics and Gynecology
• Infectious Diseases
• Perinatal Medicine

Background:

• Untreated asymptomatic bacteriuria (ASB) in pregnancy can lead to acute pyelonephritis in up to 30% of mothers.
• ASB may be linked to preterm birth or serve as a marker for socioeconomic factors associated with low birth weight.

Purpose of the Study:

• To evaluate the impact of antibiotic therapy for ASB on persistent bacteriuria during pregnancy.
• To assess the effect of ASB treatment on the risk of preterm delivery.
• To determine the influence of ASB treatment on the incidence of pyelonephritis.

Main Methods:

• Systematic review of randomized controlled trials (RCTs) from the Cochrane Pregnancy and Childbirth Group trials register (searched December 2000).
• Included RCTs compared antibiotic treatment versus placebo or no treatment for pregnant women with ASB identified via antenatal screening.
• Trial quality was assessed, though overall quality was not strong.

Main Results:

• Antibiotic treatment significantly cleared asymptomatic bacteriuria (odds ratio 0.07; 95% CI 0.05-0.10).
• The incidence of pyelonephritis was substantially reduced (odds ratio 0.24; 95% CI 0.19-0.32).
• A reduction in preterm delivery or low birth weight was observed (odds ratio 0.60; 95% CI 0.45-0.80).

Conclusions:

• Antibiotic treatment is effective in preventing pyelonephritis during pregnancy.
• While a reduction in preterm delivery was noted, this association requires cautious interpretation due to potential confounding factors.