Treatment of Urinary Tract Infections in Pregnant Women

Diagnosis and Evaluation

The European Urology guidelines recommend always performing a urine culture before initiating antibiotic treatment in pregnant women with suspected urinary tract infections 1
Asymptomatic bacteriuria in pregnant women should be treated, as these patients have a 20-30 times higher risk of developing pyelonephritis during pregnancy compared to women without bacteriuria, according to the Clinical Infectious Diseases guidelines 3
Treatment of asymptomatic bacteriuria in pregnant women reduces the risk of pyelonephritis from 20-35% to 1-4%, as stated in the Clinical Infectious Diseases guidelines 3

The European Urology guidelines recommend nitrofurantoin macrocrystals as a first-line treatment, with a dosage of 50-100 mg four times a day for 5 days 1, 2
The European Urology guidelines also recommend nitrofurantoin monohydrate or macrocrystals, with a dosage of 100 mg twice a day for 5 days 1, 2
Fosfomycin trometamol is recommended as an alternative, with a single dose of 3 g for uncomplicated cystitis, according to the European Urology guidelines 1, 2
Cefalosporins, such as cefadroxil, are recommended as an alternative, with a dosage of 500 mg twice a day for 3 days, if the local resistance of E. coli is less than 20%, as stated in the European Urology guidelines 1, 2
Trimethoprim is recommended as an alternative, with a dosage of 200 mg twice a day for 5 days, but not in the first trimester, according to the European Urology guidelines 1, 2
Trimethoprim-sulfamethoxazole is recommended as an alternative, with a dosage of 160/800 mg twice a day for 3 days, but not in the last trimester, as stated in the European Urology guidelines 1, 2

The European Urology guidelines recommend that the choice of antibiotic treatment should be guided by the susceptibility patterns of the etiological pathogens, efficacy for the particular indication, tolerability, and adverse effects 1, 2
Aminoglycosides, such as amikacin, have potential nephrotoxicity and ototoxicity, and should be used with caution during pregnancy, and only when the benefits clearly outweigh the risks, as stated in The Journal of Urology guidelines 5

For uncomplicated cystitis, a short course (3-5 days) of the recommended antibiotics is recommended, according to the European Urology and Annals of Internal Medicine guidelines 1, 4
For asymptomatic bacteriuria in pregnancy, a comparative study showed similar results between 14 days of nitrofurantoin and continuous treatment throughout pregnancy, as stated in the Clinical Infectious Diseases guidelines 3

The European Urology guidelines recommend performing a urine culture 7 days after completing treatment to confirm cure, but this is not directly cited, however, it is recommended to perform a urine culture with antimicrobial susceptibility testing in women with symptoms that do not resolve at the end of treatment or that recur within 2 weeks 2
In this situation, it should be assumed that the infecting organism is not susceptible to the originally used agent, and a 7-day regimen with another agent should be considered, as stated in the European Urology guidelines 2