Your baby may pass mucus in their stool as part of the natural digestive process. But certain health conditions, such as an allergy or infection, can also cause mucus in their poop.
Because their diet is liquid in the first months of life, babies have stool that doesn’t resemble that of older children or adults.
Sometimes, mucus in an infant’s stool is part of a normal process. However, it can also indicate an underlying infection or medical condition, such as an allergy.
However, mucus that occurs with concerning symptoms like blood in stool, vomiting, and lethargy may require emergency medical attention.
Read on to learn the potential causes of mucus in a baby’s poop and when a parent should contact a doctor.
Mucus in baby poop isn’t always cause for concern and can often be considered “normal” baby poop. The intestines naturally secrete mucus to help the stool pass more effectively.
Sometimes, a baby may pass some of this mucus in their stool without any underlying condition. The mucus can look like slimy streaks or strings, or it can be jelly-like in appearance.
Babies who are breastfed may be more likely to have mucus in their poop because their stool passes through their intestines relatively quickly.
However, certain medical conditions can cause mucus in stool and diarrhea, including infections and allergies.
Viral or bacterial infection
A viral or bacterial infection (stomach flu) can irritate the intestines and lead to inflammation. This can cause increased mucus in a baby’s poop.
Additional symptoms that could indicate infection include:
- fever
- irritability
- vomiting
Babies with an infection may also have green stool. If the irritation is severe, some blood may even be present.
With a bacterial infection, there is often blood in the stool along with mucus.
Food allergy
Food allergies can cause inflammation in the digestive tract. Inflammation usually increases mucus secretion, which leads to more mucus in a baby’s stool. These symptoms typically appear within a baby’s first two months of life. Possible indicators a baby may have a food allergy include:
- being fussy and hard to console
- vomiting
- bloody stool
- increased gas
Cystic fibrosis
Babies with cystic fibrosis may have increased amounts of mucus as a side effect of this condition. The mucus tends to be foul-smelling and greasy in appearance. The infant may also not gain enough weight and have delayed growth related to cystic fibrosis.
Cystic fibrosis also causes excess mucus to develop in organs, especially the lungs, pancreas, liver, and intestines.
Because cystic fibrosis can interfere with a child’s digestion, a doctor may recommend specific enzymes for treatment. If a baby with cystic fibrosis cannot gain enough weight, sometimes doctors recommend a feeding tube for infants, such as a gavage or a gastronomy tube (G-tube), to provide nutrition.
Malabsorption
If a baby isn’t properly absorbing the nutrients, like fat, in their food, excess fat may leave the body through the stool. This is known as steatorrhea. Steatorrhea results in stool that is unusually foul-smelling and oily. It may be confused with stool containing mucus.
It can potentially indicate issues with the liver or pancreas. It may also indicate conditions like cystic fibrosis or celiac disease in babies who have begun to eat solid foods. Celiac disease is an autoimmune disease that’s triggered by consuming gluten, a protein found in wheat.
Intussusception
Intussusception is a serious medical condition that can occur when an infant’s intestines slide into each other, a process known as “telescoping.” This is a medical emergency because blood flow is lost to the intestine, and the intestine can become blocked. It requires immediate medical attention.
As a result, a baby may only be able to pass mucus that has been excreted below the blocked area. The stool often resembles dark red jelly. Other symptoms of intussusception include:
- abdominal pain that comes and goes
- vomiting
- blood in the stool
- lethargy or extreme sleepiness
The specific treatment for mucus in baby’s poop depends on the underlying cause.
Infection
A doctor may recommend supportive treatment for a baby with a viral stomach infection. This can include fluids to prevent dehydration and medications to keep the fever down.
Bacterial infections require antibiotic medication to resolve the infection.
Allergies
If allergies are the underlying cause of mucus in baby poop, a doctor may recommend an elimination diet for the breastfeeding parent. Examples include a milk protein allergy, which may be managed by eliminating cow’s milk from your diet. If a baby is formula-fed, a doctor may recommend switching formulas to a hydrolyzed option.
Celiac disease
If your baby may have celiac disease, diet changes involve eliminating gluten-containing foods from their diet, such as those containing wheat or barley.
Intussusception
If intussusception is the underlying cause of mucus in baby poop, a doctor will likely recommend surgery to correct the intestinal overlap. This is an emergency and requires immediate medical attention.
In some instances, they may be able to use an enema to promote the “straightening out” of the intestines. This involves pushing water, air, or barium through the rectum and is usually performed during an X-ray or ultrasound to confirm reduction.
Whatever the approach to intussusception, prompt treatment is vital to prevent blood flow loss to the intestines. Otherwise, an infant is at greater risk for bowel perforation (a hole in the intestine).
The condition isn’t usually a cause for concern as long as your baby is behaving as they typically do and doesn’t have any indicators of infection or illness, such as:
- inconsolable fussiness
- fever
- blood in the stool
- vomiting
However, some causes may require medical attention.
You should continue to monitor the baby’s stool. If your baby is continually having stool that contains mucus and you’re concerned, note their symptoms and contact their pediatrician. Contact the infant’s doctor if the baby:
- has symptoms of infection or illness along with mucus in their poop
- is refusing fluids or drinking minimal fluids and starts to appear dehydrated (not crying tears or having few wet diapers)
- has red, bloodlike tinges in their poop
- is acting ill without a known reason
The doctor can direct you to the emergency room if necessary.
In most instances, mucus in baby poop isn’t a cause for concern. It can be a normal by-product of digestion, especially given the fast digestion that babies usually have.
Parents are likely to notice that a baby has mucus in stool one day, then doesn’t on another. Mucus in stool usually goes away as a baby gets older and solid foods are introduced. At this time, the stool starts to become more formed.
However, if a baby is acting ill, has blood in its stool, or is having prolonged poor feeding episodes, a parent should seek medical attention.