Why Is There Blood in My Baby’s Stool


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If there’s blood in your baby’s stool, you’re likely to get a huge fright. There are a number of reasons for it, but the good news is that it’s not usually an emergency situation. You should obviously consult your doctor, but in the meantime, here are a few reasons your baby might have blood in their stool.


Allergies to food can cause blood in the stool, often with mucus. The baby might develop allergies to cow’s milk and formula, oats, barley, rye, or wheat. The problem might develop as a result of certain supplements. Some vitamin supplements, for example, contain gluten from barley malt. This could cause blood in the stool.

Food allergies can cause food protein-induced enterocolitis syndrome and allergic colitis, both of which are caused by allergies to certain proteins in food. The symptoms are vomiting and bloody diarrhea in infants.

Anal fissure

An anal fissure is a tear in the lining of the anus that tends to bleed a little, leaving blood in the stool and diaper. They are common in infants, and experts are still not sure why. A common belief is that exclusively breastfed babies have runnier stools, leading to abrasion of the anal lining.

So, a baby with diarrhea is more likely to have an anal fissure, leading to blood in the stool. Also, babies get constipated sometimes, so that when they pass a hard stool, the anal sphincter (muscle) becomes over-stretched. This also causes abrasion of the anal lining and bleeding.


There are several infections that can lead to blood in the baby’s stool. If there’s blood as well as diarrhea, it could be an intestinal infection caused by bacteria like salmonella, campylobacter, or shigella.

These cause intestinal inflammation and bleeding. A Streptococcal infection around the anus could lead to a fissure and blood in the stool. Sometimes, the stool might be green because of blood from infection-induced diarrhea.


Colitis is the inflammation of the inner lining of the large intestine (colon). If colitis is present in infants and newborns, it’s known as pediatric ulcerative colitis. The result is small lesions in the colon that might or might not cause pain, but which can certainly cause blood in the baby’s stool. Experts do not know what causes pediatric ulcerative colitis, but genetics are suspected to play a major role.

Another form of colitis that can cause blood in the stool is necrotizing enterocolitis. This causes blood in a premature baby’s stool because of the baby’s underdeveloped immune system, making them susceptible to infections. In this condition, bacteria invade the intestinal walls, leading to inflammation and blood in the stool.

Crohn’s disease

Crohn’s disease is an inflammatory disease very similar to colitis, and which affects the large intestine. In infants, it’s known as pediatric Crohn’s disease.

It’s not known why some babies develop the disease, but it seems that genetics is once again implicated. It has been noted that in families with adult Crohn’s disease, infants are more likely to develop it.

But before you panic

The redness in your baby’s stool could also come from something she or he ate. In fact, different foods can lead to stools ranging in color from black to red, making it seem as if there is blood in the stool. These are some foods that might cause red stools in your baby:

  • Beets
  • Red gelatine
  • Tomatoes
  • Cranberries

Iron supplements can also turn your baby’s stool a reddish color, and some medications such as Cefdinir, which is used for the treatment of otitis media, can do the same. Of course, your baby could be suffering from a gastric complaint without the presence of blood in the stool. In any case, a visit to the doctor is in order when you detect blood or redness in the stool unless you can rule out food as the cause.