Asymptomatic bacteriuria in pregnancy: to treat or not to treat?

Introduction. Urinary tract infections (UTIs) are the most common extragenital pathology in pregnant women and are associated with a high risk of obstetric and neonatal complications. Attention is paid to asymptomatic bacteriuria (ASB), which may lead to the development of gestational pyelonephritis. Despite the availability of clinical guidelines, the timing of screening, the need for ASB treatment, and the choice of antimicrobial therapy remain controversial. The lack of consensus within the international medical community, as well as discrepancies in national regulatory documents, underscores the need for further study of this problem.

Objective. To evaluate the effectiveness of ASB treatment in pregnant women in real-world clinical practice.

Materials & methods. A prospective analysis of pregnancy outcomes and delivery records was performed in 150 pregnant women aged 18 to 42 years. All patients were divided into three groups: group 1 (n = 43) included women who received treatment for ASB; group 2 (n = 77) included pregnant women who declined treatment for ASB; group 3 (n = 30) included patients who had not been screened for ASB. The study included an analysis of clinical and anamnestic data, urine culture results, renal ultrasonography, and pregnancy and delivery outcomes.

Results. The groups were comparable in age and anthropometric parameters, but differed significantly in the number of pregnancies, deliveries, and gynaecological surgeries. In group 1, monomicrobial growth was detected in 81.4% of the first urine cultures and 72.1% of the second; in group 2, the corresponding values were 72.7% and 80.5%. In group 1, ASB treatment consisted of antibiotics (25.6%), Canephron (62.8%), or their combination (11.6%). Despite treatment, acute pyelonephritis developed in 7 (16.3%) patients in group 1, which was higher than in group 2, where acute UTI episodes were recorded in 3 (3.9%) women. No urological complications were observed in group 3. Vaginal delivery predominated over caesarean section in all groups. All newborns had Apgar scores of 7 – 8.

Conclusion. In this study, ASB treatment did not reduce the incidence of acute pyelonephritis in pregnant women compared with the untreated group. These findings suggest the need to reconsider approaches to ASB diagnosis, introduce methods for identifying uropathogenic taxa, and search for inflammatory biomarkers to define selective groups of pregnant women who may benefit from antibacterial therapy. Randomised controlled trials are required to individualise management strategies in this patient population.

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