What is the recommended treatment for a urinary tract infection (UTI) during pregnancy?

Treatment of Urinary Tract Infections During Pregnancy

For pregnant women with UTIs, nitrofurantoin is the first-line treatment option, except during the first trimester, while cephalosporins (e.g., cefadroxil) are appropriate alternatives throughout pregnancy. 1

First-Line Treatment Options

Nitrofurantoin

• Dosing: 100 mg twice daily or 50-100 mg four times daily
• Duration: 5 days
• Contraindication: Should not be used in first trimester of pregnancy
• Efficacy: Highly effective for lower UTIs with minimal resistance development
• Safety profile: Long history of safe use in pregnancy (except first trimester)

Cephalosporins (e.g., cefadroxil)

• Dosing: 500 mg twice daily
• Duration: 3 days
• Indication: Safe throughout all trimesters of pregnancy
• Consideration: Use when local E. coli resistance is <20%

Alternative Options

Fosfomycin trometamol

• Dosing: 3 g single dose
• Advantage: Convenient single-dose regimen
• Efficacy: Comparable to nitrofurantoin for uncomplicated UTIs and asymptomatic bacteriuria in pregnancy 2

Treatment Considerations

1. Urine Culture Requirement

   • Always obtain urine culture before initiating treatment in pregnant women 1
   • Essential for confirming diagnosis and guiding therapy based on susceptibility

2. Medications to Avoid

   • Trimethoprim: Contraindicated in first trimester
   • Trimethoprim-sulfamethoxazole: Contraindicated in last trimester
   • Fluoroquinolones: Not recommended during pregnancy

3. Follow-up

   • Perform follow-up urine culture 1-2 weeks after completing treatment
   • Ensures complete eradication of infection

Special Scenarios

Asymptomatic Bacteriuria

• Must be treated in pregnancy (unlike non-pregnant patients)
• Same antibiotic options as symptomatic UTI
• Screening and treatment reduces risk of pyelonephritis and adverse pregnancy outcomes 3

Recurrent UTIs in Pregnancy

• For women with history of recurrent UTIs during pregnancy:
  • Consider prophylactic antibiotics
  • Options include postcoital prophylaxis with nitrofurantoin 50 mg or cephalexin 250 mg 4
  • Prophylaxis significantly reduces UTI recurrence during pregnancy

Clinical Pearls and Pitfalls

1. All UTIs in pregnancy require treatment - including asymptomatic bacteriuria, unlike in non-pregnant women 3

2. Avoid treatment delays - UTIs in pregnancy can rapidly progress to pyelonephritis, which increases risks of preterm labor and low birth weight

3. Resistance considerations - Choose antibiotics based on local resistance patterns when possible

4. Duration matters - Single-dose therapy has lower success rates than 3-5 day regimens in pregnancy 5

5. Monitor for recurrence - Pregnant women have higher rates of recurrent UTIs due to physiological changes in the urinary tract

By following these evidence-based recommendations, clinicians can effectively manage UTIs during pregnancy while minimizing risks to both mother and fetus.