What does hematuria during a menstrual cycle indicate, and what are the necessary next steps?

Hematuria During Menstrual Cycle: Evaluation and Management

Hematuria attributed to menstruation is a diagnosis of exclusion that requires confirmation after the menstrual cycle ends, as it may mask significant underlying urologic or renal pathology. 1

Understanding Menstrual-Related Hematuria

When hematuria is detected during menstruation, it's important to recognize:

• Menstrual blood can contaminate urine samples, creating a false impression of hematuria
• True hematuria requires confirmation with microscopic examination showing ≥3 red blood cells per high-power field 1
• Dipstick positivity for blood should always be confirmed microscopically due to limited specificity (65-99%) 1

Proper Evaluation Approach

1. Initial Assessment:

   • Repeat urinalysis after menstruation has completely ended 2, 1
   • If hematuria persists after menstruation, proceed with full evaluation
   • Do not assume menstruation is the cause without proper follow-up testing

2. If Hematuria Persists After Menstruation:

   • Complete laboratory workup including:
     • Complete blood count
     • Serum creatinine and BUN
     • Urinalysis with microscopic examination
     • Urine culture if infection is suspected 1

3. Risk Stratification:

   • The American Urological Association defines three risk categories for patients with hematuria:
     • Low (0-0.4%)
     • Intermediate (0.2-3.1%)
     • High (1.3-6.3%) 1
   • Risk factors include age >35 years, smoking history, and occupational exposure to chemicals 1

Common Pitfalls to Avoid

• Pitfall #1: Assuming menstruation is the cause without confirmation

  • Always repeat urinalysis after menstruation has ended 2, 1

• Pitfall #2: Relying solely on dipstick testing

  • Microscopic confirmation is essential 1

• Pitfall #3: Inadequate follow-up

  • Even if initial hematuria resolves after menstruation, consider annual urinalysis for monitoring 1

• Pitfall #4: Missing gross hematuria history

  • Specifically ask about any episodes of visible blood in urine, as this carries a much higher risk of malignancy (30-40%) 1

When to Refer

Urologic referral is indicated for:

• Persistent hematuria after menstruation ends
• Gross hematuria at any time
• Age >60 years with unexplained hematuria
• Recurrent urinary tract infections 1

Remember that gross hematuria carries a 30-40% risk of urinary tract malignancy and requires prompt evaluation, regardless of timing with menstruation 1. Asymptomatic microscopic hematuria without proteinuria rarely indicates significant renal disease but still warrants proper follow-up 1.