A Cochrane review «Antibiotics for asymptomatic bacteriuria in pregnancy»1 «Smaill FM, Vazquez JC. Antibiotics for asymptomatic bacteriuria in pregnancy. Cochrane Database Syst Rev 2019;2019(11):. »1 included 15 studies with over 2000 women. Antibiotic treatment compared to placebo or no treatment was effective in clearing asymptomatic bacteriuria. The incidence of pyelonephritis, preterm delivery, and low birthweight babies was reduced (table «Antibiotics for asymptomatic bacteriuria in pregnancy»1). There were very limited data on which to estimate the effect of antibiotics on other infant outcomes, and maternal adverse effects were rarely described.
| Outcome | Relative effect (95% CI) | Risk with no treatment | Risk with antibiotics (95% CI) | № of participants (studies) Certainty of the evidence |
|---|---|---|---|---|
| Development of pyelonephritis | RR 0.24 (0.13 to 0.41) | 199 per 1000 | 48 per 1000 (26 to 82) | 2017 (12) Low |
| Preterm birth < 37 weeks | RR 0.34 (0.13 to 0.88) | 174 per 1000 | 59 per 1000 (23 to 153) | 327 (3) Low |
| Birthweight < 2500 g | RR 0.64 (0.45 to 0.93) | 136 per 1000 | 87 per 1000 (61 to 126) | 1437 (6) Low |
Comment: The quality of evidence was downgraded by severe limitations in study quality (high or unclear risk of bias in most studies).
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