The 4 Most Common Causes of Blood in Diaper

  • Urinary crystals
    • Will be guaiac negative
    • Common in first few weeks of life
  • Vaginal bleeding
    • Common in newborn females as they withdraw from maternal estrogen
  • Maternal blood
    • Swallowed during birthing process
    • Breastfeeding with cracked/bleeding nipples
  • Anal fissures
    • Common and will improve on its own

Basic Approach

  • Step 1: Check if guaiac positive
    • If negative, it’s not blood
    • Urinary crystals, food coloring, etc
  • Step 2: Consider vaginal bleeding
  • Step 3: Perform apt test
    • Diagnoses maternal blood
  • Step 4: Check for anal fissure
    • Self resolve
  • Step 5: Expand the differential diagnosis
    • Necrotizing enterocolitis
    • Intussusception
    • Cow’s milk allergy
    • Colitis
    • Red Food Dye

Additional Reading