Comparative study of amoxicillin-clavulanic acid and cephalexin in the treatment of bacteriuria during pregnancy.

A comparative clinical trial of amoxicillin-clavulanic acid and cephalexin was carried out in 80 women with bacteriuria of pregnancy. Treatment was randomly allocated and consisted of either one tablet of amoxicillin plus clavulanic acid (250 and 125 mg, respectively) three times daily or cephalexin (250 mg) three times daily for 7 days. Overall bacteriological cure rates at 2 weeks were 77% in the amoxicillin-clavulanic acid group and 74% in the cephalexin group. At 6 weeks the respective rates were 76 and 60%. Twenty-five episodes of infection were with ampicillin-resistant strains; cure rates were 82% (2 weeks) and 80% (6 weeks) in the amoxicillin-clavulanic acid group and 85 and 64%, respectively, in the cephalexin group. Differences in cure rates were not statistically significant. No significant difference in the rate of side effects was found. In particular, no toxicity to the fetus was seen which could be ascribed to either drug. Amoxicillin-clavulanic acid would appear to be a safe and effective treatment for bacteriuria of pregnancy.