What is the recommended treatment for urinary tract infections (UTIs) in pregnancy?

Treatment of UTI in Pregnancy

Pregnant women with UTIs should be treated with nitrofurantoin (except near term), fosfomycin trometamol as a single dose, or cephalosporins (such as cefixime) for 5-7 days, with treatment guided by urine culture results. 1

Diagnostic Approach

• Always obtain a urine culture in pregnant women with UTI symptoms before initiating treatment to confirm diagnosis and guide antibiotic selection 2, 1
• This differs from non-pregnant women where empiric treatment without culture is often acceptable 2

First-Line Treatment Options

The European Association of Urology guidelines and recent evidence support three primary antibiotic choices 2, 1:

Nitrofurantoin

• Dosing: 50-100 mg four times daily OR 100 mg twice daily for 5 days 2
• Critical caveat: Safe throughout pregnancy EXCEPT avoid in the last trimester due to risk of hemolytic anemia in the newborn 1
• Achieves high urinary concentrations and maintains low resistance rates 3

Fosfomycin Trometamol

• Dosing: 3 grams as a single oral dose 2, 1
• Advantage: Single-dose administration improves compliance and is equally effective as multi-day regimens 1, 4
• Particularly useful for uncomplicated cystitis in pregnancy 2

Cephalosporins

• Preferred agent: Cefixime (third-generation cephalosporin) 1, 5
• Alternative: Cefadroxil 500 mg twice daily for 3 days 2
• Rational choice due to high sensitivity of E. coli, good safety profile, and compliance 5

Treatment Duration

• Standard duration: 5-7 days for symptomatic UTIs in pregnancy 1
• Avoid shorter courses (1-3 days) as they are not recommended for pregnant women 1
• Single-dose fosfomycin is the exception to this rule 2, 1

Critical Medications to Avoid

Trimethoprim-Sulfamethoxazole

• Contraindicated in first trimester due to potential teratogenic effects (risk of anencephaly, heart defects, orofacial clefts) 2, 1, 6
• Contraindicated in third trimester due to risk of neonatal hyperbilirubinemia 2, 1
• Despite 80% cure rates, the timing restrictions make it problematic 7

Fluoroquinolones

• Absolutely contraindicated throughout pregnancy 1
• Despite being commonly prescribed (ciprofloxacin was the second most prescribed antibiotic in one 2014 study), this represents inappropriate prescribing 6

Special Considerations

Asymptomatic Bacteriuria in Pregnancy

• Must be treated in pregnant women (unlike non-pregnant populations where treatment is generally not recommended) 2, 1
• Use standard short-course treatment or single-dose fosfomycin trometamol 2
• Screening and treatment prevents progression to pyelonephritis, preterm labor, and low birth weight 6

Recurrent UTIs in Pregnancy

• Prophylaxis option: Daily low-dose antibiotics can be used in select cases with frequent recurrences 1
• Post-coital prophylaxis with cephalexin 250 mg or nitrofurantoin 50 mg has proven highly effective, reducing UTI incidence from multiple infections to single episodes during pregnancy 3

Common Pitfalls to Avoid

• Do not use antibiotics that fail to achieve adequate urinary concentrations (e.g., certain macrolides) 1
• Do not classify all pregnant women with UTI as "complicated" - this leads to unnecessary broad-spectrum antibiotic use 2
• Do not treat asymptomatic bacteriuria outside of pregnancy - pregnancy is one of the few indications where treatment is mandatory 2, 1
• Avoid amoxicillin/clavulanate in women with premature rupture of membranes as prophylactic treatment may be associated with increased risk of necrotizing enterocolitis in neonates 8

Post-Treatment Monitoring

• Repeat urine culture 7 days after completing therapy to document cure 7
• If symptoms persist despite treatment, obtain repeat culture before prescribing additional antibiotics 2