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Worried About Blood in Your Baby’s Stool?

Seeing blood in baby poop, red streaks in baby stool, or blood in a newborn stool can be upsetting. Get clear, parent-friendly guidance to understand what the color and pattern may mean, when it may be monitored, and when your baby should be seen promptly.

Start with what the blood looks like

Answer a few questions about your baby’s stool, feeding, and symptoms to get personalized guidance for blood in baby stool and what steps may make sense next.

What does the blood in your baby’s stool look like right now?
Takes about 2 minutes Personalized summary Private

Why blood in baby stool can happen

Blood in infant stool can come from several different causes, and the appearance matters. Bright red streaks on the outside of the stool may happen with a small anal fissure, especially if your baby has been straining. Blood mixed into the stool, dark red blood, or black tar-like stool can point to bleeding higher in the digestive tract and deserves closer attention. In some babies, blood in the diaper stool may also be linked to milk protein irritation, swallowed maternal blood, infection, or constipation. Because the possibilities are different, it helps to look at the color, amount, and whether your baby has other symptoms.

What details matter most

Color and pattern

Bright red streaks in baby stool often suggest a lower source, while dark red, maroon, or black stool can suggest bleeding from higher up in the digestive system.

How your baby is acting

A baby who is feeding well and otherwise comfortable may need different guidance than a baby with vomiting, fever, belly swelling, unusual sleepiness, or signs of pain.

Recent feeding and stool changes

New formula, dairy exposure, constipation, diarrhea, or frequent stools can all help explain why a baby bowel movement has blood and what to do next.

When parents should seek urgent care

Black or tar-like stool

Black stool that is not clearly explained by iron or another known cause can be a warning sign and should be evaluated promptly.

Blood with concerning symptoms

Get urgent medical care if blood in baby poop happens along with vomiting, fever, a swollen belly, poor feeding, trouble waking, weakness, or your baby seems very unwell.

Large amounts or repeated bleeding

If you see more than a small streak, the bleeding keeps happening, or the diaper has obvious blood, your baby should be assessed promptly.

Common causes that may be considered

Small anal tear

A fissure can happen after straining or passing a firm stool and may cause a small amount of bright red blood on the stool or diaper.

Milk protein irritation

Some babies with infant stool with blood also have mucus, fussiness, eczema, or feeding-related symptoms that raise concern for protein intolerance or allergy.

Infection or intestinal inflammation

If your baby has diarrhea, fever, seems uncomfortable, or the blood is mixed into the stool, a clinician may consider infection or another digestive cause.

Frequently Asked Questions

Is a small streak of bright red blood in baby stool always an emergency?

Not always. A tiny bright red streak on the outside of the stool can happen with a small anal fissure, especially after straining. But if it keeps happening, the amount increases, or your baby has other symptoms, your baby should be evaluated.

What does black or tar-like stool mean in a baby?

Black or tar-like stool can sometimes suggest digested blood from higher in the digestive tract. In a newborn, there can be special situations such as swallowed maternal blood, but black stool should be taken seriously and discussed with a clinician promptly.

Can milk allergy cause blood in infant stool?

Yes. In some babies, milk protein irritation or allergy can lead to blood or mucus in the stool. This is more likely if there are feeding issues, fussiness, eczema, or ongoing stool changes, but a clinician should help confirm the cause.

Should I take a photo of the diaper if my baby poop has blood?

Yes, if you can do so safely and comfortably. A photo can help a clinician understand the color, amount, and pattern of the blood, especially if the stool looks different later.

Get personalized guidance for blood in your baby’s stool

Answer a few questions about what you’re seeing right now to get a focused assessment, understand possible causes, and know when to seek care.

Answer a Few Questions

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