Asymptomatic bacteriuria in pregnancy - Balancing benefits and risks in urological practice
Asymptomatic bacteriuria (ABU) in pregnancy affects approximately 2–10% of pregnant women. While ASB itself is not symptomatic, its potential consequences can be severe. If left untreated, ABU can progress to acute pyelonephritis in up to 30% of cases, increasing the risk of preterm birth, low birth weight, and perinatal complications. As a result, screening and treatment of ABU have traditionally been part of prenatal care.
However, emerging concerns about antimicrobial resistance (AMR) and antibiotic stewardship have led to diverging recommendations between medical specialties. While some guidelines advocate universal screening and treatment, others recommend a risk-based approach to minimise unnecessary antibiotic exposure.
Current guidelines and clinical uncertainty
The EAU Guidelines and infectious disease guidelines recommend targeted screening for ABU, primarily in high-risk populations such as women with a history of recurrent urinary tract infections (UTIs) or anatomical abnormalities2. In contrast, obstetric guidelines, including those from the US Preventive Services Task Force (USPSTF) and multiple national gynaecological societies, support universal screening at 12–16 weeks of gestation.
Despite these recommendations, real-world clinical practice varies significantly. Our ongoing multinational survey of urologists in Germany, Austria, and Switzerland suggests:
- Many urologists perform ABU screening selectively, often restricted to women with known risk factors.
- Treatment decisions are inconsistent, with some clinicians opting for short-course antibiotic regimens (3-5 days) while others extend treatment periods extending beyond guideline recommendations.
- Concerns about overtreatment - particularly regarding potential harms to the foetus, disruptions in maternal microbiota, and AMR development - influence prescribing behaviours.
The impact of treating ABU: Finding the right balance
While treatment of ABU has been shown to reduce the incidence of pyelonephritis and associated pregnancy complications, it is not without risks:
- Antibiotic use during pregnancy has been linked to disruptions in neonatal gut microbiota, which may have long-term health implications.
- The rise of antimicrobial resistance (AMR) is a major global challenge, making judicious antibiotic prescribing critical.
- Adverse drug reactions, including hypersensitivity, gastrointestinal side effects, and C. difficile infections, must be considered when treating ABU.
Given these factors, a more nuanced approach to ABU management is needed - one that considers individual patient risks, microbiological findings, and antimicrobial resistance patterns.
Survey invitation: Why your participation matters
To better understand how urologists’ approach ABU management in clinical practice, we have initiated a multinational survey. The goal is to capture clinical decision-making patterns, identify barriers to guideline adherence, and inform future recommendations to achieve a more standardised, evidence-based approach.
We invite all general practitioners, gynaecologists and urologists to participate in the anonymous survey, which requires 3-5 minutes only, and respondents will contribute to a scientific publication. Participate in the short survey here.
Your input will help bridge the gap between guidelines and clinical reality, ultimately improving maternal and fetal outcomes. For further enquiries, please contact Dr. Fabian Stangl by email.
References
- Smaill FM, Vazquez JC. Antibiotics for asymptomatic bacteriuria in pregnancy. Cochrane Database Syst Rev. Nov 25 2019;2019(11)doi:10.1002/14651858.CD000490.pub4
- Kranz J, Bartoletti R, Bruyère F, et al. European Association of Urology Guidelines on Urological Infections: Summary of the 2024 Guidelines. European Urology. 2024;
- Davidson KW, Barry MJ, Mangione CM, et al. Screening for gestational diabetes: US preventive services task force recommendation statement. Jama. 2021;326(6):531-538.