Introduction. Asymptomatic bacteriuria (AB) is a form of urinary tract infection (UTI) that occurs without any symptoms. Its incidence fluctuates around 6%. The generally accepted paradigm suggests the need to treat AB, but this statement is mainly based on research data from the 1950-70 years.

Objective. To study the effect of antimicrobial drugs in the treatment of AB in pregnant women on obstetric and perinatal outcomes and urological complications. Materials and methods. A multicenter retrospective study was conducted involving 182 pregnant women aged 18 to 45 years with established AB. During the study, the pregnant women were divided into 4 groups with different criteria; Group 1 (n=44) received treatment with protected penicillins; Group 2 (n=47) received treatment with fosfomycin; Group 3 (n=40) the drug of choice was cephalosporin; Group 4 (n=51) patients with normal pregnancy.

Results. No significant differences were found in mean age, obstetric outcomes, and urological complications. Preterm birth was more common in Group 1 compared to Group 2, preeclampsia was also more common in Group 1, but Group 2 tended to have an increased incidence of the complication. Low fetal weight was more common in Group 1 and Group 3, but fetal hypoxia was more common in Group 2, and it was not possible to associate this complication with antibiotic use.

Conclusion. Further studies are needed to assess both the association of AB in pregnant women with gestational pyelonephritis and to determine the benefits of prescribing antimicrobials for this type of UTI.