Digestive

Blood in Baby's Stool

Medically reviewed by Dr. Sarah Chen, MD, FAAP · Board-Certified Pediatrician

Content reviewed against published AAP, AAP, NASPGHAN guidelines

Editorial policy

Last reviewed:

Digestive issues are common in infants and toddlers. If your baby is experiencing blood in baby's stool, here is what you need to know.

The short answer

Seeing blood in your baby's stool is understandably alarming, but the most common cause in young babies is a small anal fissure (a tiny tear from passing stool) or swallowed maternal blood from cracked nipples during breastfeeding. However, blood in stool always deserves medical evaluation to rule out less common but important causes like a cow's milk protein allergy or infection.

Key takeaways

  • Seeing blood in your baby's stool is understandably alarming, but the most common cause in young babies is a small anal fissure (a tiny tear from passing stool) or swallowed maternal blood from cracked nipples during breastfeeding. However, blood in stool always deserves medical evaluation to rule out less common but important causes like a cow's milk protein allergy or infection.
  • Usually normal when: You see a single small streak of bright red blood on the outside of a hard stool, likely from a small fissure
  • Call your doctor if: Your baby has large amounts of blood in the stool, bloody diarrhea, or dark red currant jelly-like stools, which could indicate intussusception or another serious condition
  • Varies by age — see the age-by-age breakdown below
“The biggest concern with vomiting is dehydration. Young children can become dehydrated quickly, so it's important to replace fluids. Offer small amounts of an oral rehydration solution frequently.”
— Vomiting in Children, American Academy of Pediatrics (AAP)

Thousands of parents search for this exact thing. You are not alone.

What Parents Should Know

According to AAP, NASPGHAN guidelines, seeing blood in your baby's stool is understandably alarming, but the most common cause in young babies is a small anal fissure (a tiny tear from passing stool) or swallowed maternal blood from cracked nipples during breastfeeding. However, blood in stool always deserves medical evaluation to rule out less common but important causes like a cow's milk protein allergy or infection. At 0-3 months, in newborns, the most common causes of blood in stool are swallowed maternal blood from breastfeeding and cow's milk protein intolerance, which can cause tiny streaks of blood mixed with mucus. Anal fissures from passing stool can also cause small bright red streaks on the outside of the stool. Any blood in a newborn's stool should be evaluated by your pediatrician. It is generally considered normal when you see a single small streak of bright red blood on the outside of a hard stool, likely from a small fissure. However, you should contact your pediatrician promptly if your baby has large amounts of blood in the stool, bloody diarrhea, or dark red currant jelly-like stools, which could indicate intussusception or another serious condition.

Sources: [1], [2], [3]

Normal vs. Concerning

Usually Normal
Worth Discussing
You see a single small streak of bright red blood on the outside of a hard stool, likely from a small fissure
Your baby has large amounts of blood in the stool, bloody diarrhea, or dark red currant jelly-like stools, which could indicate intussusception or another serious condition
Your breastfed baby has a small amount of blood in stool and you have cracked or bleeding nipples
Your baby has bloody stool along with vomiting, severe abdominal pain with episodes of inconsolable screaming, or lethargy
Your baby recently ate beets, red gelatin, or tomatoes and the stool appears reddish but is not actually blood
Your baby passes black, tarry stools (not from iron supplements) which can indicate bleeding higher in the digestive tract

By Age

What to expect by age

0-3 months

In newborns, the most common causes of blood in stool are swallowed maternal blood from breastfeeding and cow's milk protein intolerance, which can cause tiny streaks of blood mixed with mucus. Anal fissures from passing stool can also cause small bright red streaks on the outside of the stool. Any blood in a newborn's stool should be evaluated by your pediatrician.

3-6 months

Cow's milk protein allergy remains a common cause in this age range, affecting about 2-3% of infants. Blood may appear as small flecks or streaks mixed with mucus. If your breastfed baby has bloody stools, your doctor may suggest you eliminate dairy from your diet for 2-4 weeks to see if symptoms improve.

6-12 months

As babies start solids, constipation may lead to hard stools that cause anal fissures and bright red blood on the surface of the stool or on the diaper. Infections from bacteria like Salmonella can also cause bloody diarrhea. Intussusception, though rare, can cause currant jelly-like stools and is a medical emergency requiring immediate attention.

12-36 months

In toddlers, the most common causes of bloody stool continue to be constipation-related fissures and infectious gastroenteritis. Allergic colitis may persist or emerge. Recurrent painless rectal bleeding could indicate a Meckel diverticulum or juvenile polyp, both of which your doctor can evaluate.

What to Tell Your Pediatrician

  • Describe when you first noticed blood in baby's stool and how it has changed over time.
  • Note your baby's current age and which age-specific patterns you are seeing.
  • Mention if you notice small streaks or flecks of blood in your baby's stool, even if your baby seems well.
  • Mention if blood in stool is accompanied by mucus, suggesting possible allergic colitis or infection.
  • Bring a list of any questions or observations you want to discuss at the appointment.

What Should You Do?

When to take action

Probably normal when...
  • You see a single small streak of bright red blood on the outside of a hard stool, likely from a small fissure
  • Your breastfed baby has a small amount of blood in stool and you have cracked or bleeding nipples
  • Your baby recently ate beets, red gelatin, or tomatoes and the stool appears reddish but is not actually blood
Mention at your next visit when...
  • You notice small streaks or flecks of blood in your baby's stool, even if your baby seems well
  • Blood in stool is accompanied by mucus, suggesting possible allergic colitis or infection
  • Your baby has recurring episodes of blood in stool, even if small amounts
  • Your breastfed baby has persistent blood-streaked stools and you want to discuss a potential dairy elimination trial
Act now when...
  • Your baby has large amounts of blood in the stool, bloody diarrhea, or dark red currant jelly-like stools, which could indicate intussusception or another serious condition
  • Your baby has bloody stool along with vomiting, severe abdominal pain with episodes of inconsolable screaming, or lethargy
  • Your baby passes black, tarry stools (not from iron supplements) which can indicate bleeding higher in the digestive tract

What You Can Do at Home

  • Keep track of when you notice blood in baby's stool — noting the time of day, duration, and any triggers can help your pediatrician.
  • Remember that you see a single small streak of bright red blood on the outside of a hard stool, likely from a small fissure — this is generally within the range of normal.
  • At 0-3 months, focus on observation rather than intervention unless your pediatrician advises otherwise.
  • Keep your baby upright for 20-30 minutes after feeding. Note any patterns between feeds and symptoms.
  • While monitoring at home, seek immediate care if your baby has large amounts of blood in the stool, bloody diarrhea, or dark red currant jelly-like stools, which could indicate intussusception or another serious condition.
Guide

Poop Color & Texture Guide

What your baby's poop color and consistency mean, and when to worry.

Milestone

Month-by-Month Development

Detailed monthly development guides from birth through 24 months.

Guide

When to Call the Doctor

General guide on when to call the pediatrician, visit urgent care, or go to the ER.

Frequently asked questions

Is blood in baby's stool normal?
Seeing blood in your baby's stool is understandably alarming, but the most common cause in young babies is a small anal fissure (a tiny tear from passing stool) or swallowed maternal blood from cracked nipples during breastfeeding. However, blood in stool always deserves medical evaluation to rule out less common but important causes like a cow's milk protein allergy or infection.
When should I call the doctor about blood in baby's stool?
Your baby has large amounts of blood in the stool, bloody diarrhea, or dark red currant jelly-like stools, which could indicate intussusception or another serious condition Your baby has bloody stool along with vomiting, severe abdominal pain with episodes of inconsolable screaming, or lethargy Your baby passes black, tarry stools (not from iron supplements) which can indicate bleeding higher in the digestive tract
When is blood in baby's stool normal?
You see a single small streak of bright red blood on the outside of a hard stool, likely from a small fissure Your breastfed baby has a small amount of blood in stool and you have cracked or bleeding nipples Your baby recently ate beets, red gelatin, or tomatoes and the stool appears reddish but is not actually blood
What causes blood in baby's stool?
Seeing blood in your baby's stool is understandably alarming, but the most common cause in young babies is a small anal fissure (a tiny tear from passing stool) or swallowed maternal blood from cracked nipples during breastfeeding. However, blood in stool always deserves medical evaluation to rule out less common but important causes like a cow's milk protein allergy or infection. Common explanations include: You see a single small streak of bright red blood on the outside of a hard stool, likely from a small fissure. Your breastfed baby has a small amount of blood in stool and you have cracked or bleeding nipples.
What should I mention to my pediatrician about blood in baby's stool?
You should mention blood in baby's stool at your next visit if: You notice small streaks or flecks of blood in your baby's stool, even if your baby seems well. Blood in stool is accompanied by mucus, suggesting possible allergic colitis or infection. Your baby has recurring episodes of blood in stool, even if small amounts.
Is blood in baby's stool normal at 0-3 months?
In newborns, the most common causes of blood in stool are swallowed maternal blood from breastfeeding and cow's milk protein intolerance, which can cause tiny streaks of blood mixed with mucus. Anal fissures from passing stool can also cause small bright red streaks on the outside of the stool. Any blood in a newborn's stool should be evaluated by your pediatrician.
Is blood in baby's stool normal at 3-6 months?
Cow's milk protein allergy remains a common cause in this age range, affecting about 2-3% of infants. Blood may appear as small flecks or streaks mixed with mucus. If your breastfed baby has bloody stools, your doctor may suggest you eliminate dairy from your diet for 2-4 weeks to see if symptoms improve.
Should I go to the ER for blood in baby's stool?
Seek emergency care if your baby has large amounts of blood in the stool, bloody diarrhea, or dark red currant jelly-like stools, which could indicate intussusception or another serious condition, or if your baby has bloody stool along with vomiting, severe abdominal pain with episodes of inconsolable screaming, or lethargy. When in doubt, call your pediatrician's after-hours line for guidance.
Does blood in baby's stool go away on its own?
In many cases, blood in baby's stool resolves on its own, especially when you see a single small streak of bright red blood on the outside of a hard stool, likely from a small fissure. By 12-36 months, in toddlers, the most common causes of bloody stool continue to be constipation-related fissures and infectious gastroenteritis. Allergic colitis may persist or emerge. Recurrent painless rectal bleeding could indicate a Meckel diverticulum or juvenile polyp, both of which your doctor can evaluate.
AAPAAPNASPGHAN

References

  1. [1]American Academy of Pediatrics. Blood in Infant's Stool. HealthyChildren.org. AAP
  2. [2]American Academy of Pediatrics. The Many Colors of Poop. HealthyChildren.org. AAP
  3. [3]North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition. Rectal Bleeding in Infants. NASPGHAN

Doctor Visit Checklist

Bring this checklist to your next pediatrician visit to discuss Blood in Baby's Stool.

Things to mention

  • Describe when you first noticed blood in baby's stool and how it has changed over time.
  • Note your baby's current age and which age-specific patterns you are seeing.
  • Mention if you notice small streaks or flecks of blood in your baby's stool, even if your baby seems well.
  • Mention if blood in stool is accompanied by mucus, suggesting possible allergic colitis or infection.
  • Bring a list of any questions or observations you want to discuss at the appointment.

Observations to share

  • You notice small streaks or flecks of blood in your baby's stool, even if your baby seems well
  • Blood in stool is accompanied by mucus, suggesting possible allergic colitis or infection
  • Your baby has recurring episodes of blood in stool, even if small amounts

Urgent signs to report immediately

  • Your baby has large amounts of blood in the stool, bloody diarrhea, or dark red currant jelly-like stools, which could indicate intussusception or another serious condition
  • Your baby has bloody stool along with vomiting, severe abdominal pain with episodes of inconsolable screaming, or lethargy
  • Your baby passes black, tarry stools (not from iron supplements) which can indicate bleeding higher in the digestive tract

My notes

From ismybabyalright.com — free, evidence-based baby health guides

All content follows our editorial policy and is reviewed against published clinical guidelines.

2,705 evidence-based guides6 authoritative medical sources5 medical advisory board members

Related Resources

Poop Color GuideEmergency ContactsBaby Tracker

Bottom line

Most cases of blood in baby's stool are normal. Talk to your pediatrician if your baby has large amounts of blood in the stool, bloody diarrhea, or dark red currant jelly-like stools, which could indicate intussusception or another serious condition.

Trust your instincts. If something feels wrong, reach out to your pediatrician. Worrying about your baby means you care — that is a good thing.

Share:FacebookX

Was this page helpful?

Related Digestive Concerns

My Baby's Belly Looks Swollen

A rounded, slightly protruding belly is completely normal in babies and toddlers due to immature abdominal muscles and their proportionally larger organs. However, if the belly becomes suddenly swollen, feels hard and tight, or is accompanied by pain, vomiting, or changes in bowel movements, it needs medical evaluation as it could signal gas buildup, constipation, or rarely, something more serious.

My Baby Has an Anal Fissure (Blood When Pooping)

A small streak of bright red blood on the surface of your baby's stool or on the diaper is most commonly caused by an anal fissure, which is a tiny tear in the skin around the anus from passing hard stool. Anal fissures are very common in babies and toddlers and usually heal on their own with simple measures like keeping stools soft. While this is rarely serious, any blood in your baby's stool should be mentioned to your pediatrician.

Can Antibiotics Damage My Baby's Gut?

Antibiotics can temporarily disrupt your baby's gut microbiome, which may cause loose stools, fussiness, or diaper rash during and shortly after treatment. However, when antibiotics are medically necessary, the benefits of treating the infection far outweigh the temporary gut disruption. Most babies' microbiomes recover within weeks to months, especially with breastfeeding and a gradual return to normal feeding patterns.

Tummy Massage for Baby Gas

Gentle abdominal massage can help relieve gas and discomfort in babies by encouraging gas to move through the intestines. The technique involves gentle clockwise circular motions on the belly (following the direction of the digestive tract), the "I Love U" stroke pattern, and gentle knee-to-tummy movements. Massage also provides comforting touch that can soothe a fussy baby.

Silent Reflux in Baby

Silent reflux occurs when stomach acid rises into the esophagus and throat but is swallowed back down rather than spit up. Babies with silent reflux may be fussy during or after feeds, arch their back, have hoarse crying, or refuse to eat, but without visible spitting up. It can be harder to diagnose than typical reflux because there is no obvious spit-up.

Bicycle Legs Technique for Gas

Bicycle legs is a simple, effective technique for helping babies pass trapped gas. Gently moving your baby's legs in a cycling motion pushes against the abdomen and helps gas move through the intestines. Combined with gentle belly massage and tummy time, it is one of the best non-medical approaches to gas relief in infants.