What is the treatment for urinary tract infections (UTIs) in pregnant women?

Management of Urinary Tract Infections in Pregnant Women

For pregnant women with UTIs, treatment with antibiotics is essential to prevent complications such as pyelonephritis, preterm labor, and low birth weight, with nitrofurantoin, β-lactams (ampicillin or cephalexin), or fosfomycin being the preferred first-line agents. 1

Diagnosis and Screening

• All pregnant women should be screened for asymptomatic bacteriuria (ASB) with a urine culture during the first trimester 2, 3
• Any presence of GBS bacteriuria during pregnancy (in any concentration) requires intrapartum antibiotic prophylaxis 2
• Laboratory personnel should report any presence of GBS in urine specimens from pregnant women 2
• Symptoms of UTI in pregnancy include:
  • Dysuria
  • Frequency
  • Urgency
  • Suprapubic pain
  • Hematuria

Treatment of UTIs in Pregnancy

First-Line Antibiotics

• Nitrofurantoin: 100 mg twice daily for 5-7 days 1
  • Avoid in G6PD deficiency and near term (>36 weeks)
• Cephalexin: 500 mg four times daily for 7 days 1
• Fosfomycin: 3 g single dose 2, 1
  • Limited clinical evaluation in pregnancy 2
• Ampicillin: For susceptible organisms

Duration of Treatment

• 4-7 days of antimicrobial therapy is recommended for ASB and cystitis in pregnancy 2
• Single-dose therapy (except fosfomycin) is less effective than short-course therapy 2
• A 7-day course is more effective than single-dose therapy in preventing adverse outcomes such as lower birth weight 2

Special Considerations

• Asymptomatic bacteriuria:

  • Must be treated in pregnancy (unlike non-pregnant women) 2, 3
  • Treatment reduces the risk of pyelonephritis (20-40% risk if untreated) 1, 3
  • Reduces risk of preterm birth and low birth weight 3

• Trimethoprim-sulfamethoxazole:

  • Avoid in first trimester due to potential risk for birth defects 4
  • Avoid in last trimester due to risk of kernicterus 2

• Fluoroquinolones:

  • Not recommended during pregnancy due to potential adverse effects on fetal cartilage development 2

Management of Complicated UTIs in Pregnancy

Pyelonephritis

• Requires hospitalization and intravenous antibiotics initially
• Preferred parenteral options 2, 3:
  • Ceftriaxone: 1-2 g daily
  • Cefotaxime: 2 g three times daily
  • Ampicillin plus aminoglycoside
  • Switch to oral therapy once clinically improved

Recurrent UTIs in Pregnancy

• Periodic screening throughout pregnancy due to high recurrence risk 1
• After initial treatment, obtain follow-up urine culture 1-2 weeks after completing antibiotics 1
• For women with history of recurrent UTIs, consider prophylactic antibiotics after treatment of acute episode

Prevention Strategies

• Increased fluid intake
• Urinate before and after sexual activity
• Proper wiping technique (front to back)
• Avoid irritating feminine products

Potential Complications of Untreated UTIs in Pregnancy

• Progression to pyelonephritis
• Preterm labor and delivery
• Low birth weight infants
• Maternal sepsis
• Increased perinatal mortality

Common Pitfalls to Avoid

1. Failure to screen: All pregnant women should be screened for ASB in the first trimester
2. Inadequate follow-up: Obtain test-of-cure cultures 1-2 weeks after treatment
3. Inappropriate antibiotic selection: Avoid trimethoprim-sulfamethoxazole in first and third trimesters
4. Untreated GBS bacteriuria: Any concentration of GBS in urine requires treatment and intrapartum prophylaxis
5. Inadequate treatment duration: Single-dose therapy (except fosfomycin) has lower cure rates in pregnancy

UTIs in pregnancy require prompt diagnosis and appropriate treatment to prevent serious maternal and fetal complications. The choice of antibiotic should consider local resistance patterns, safety in pregnancy, and the trimester of pregnancy.