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Mucus in Baby Poop

Mucus in Baby Poop

Learn about mucus in baby poop, what it means, and when to be concerned.

One common concern that many parents encounter is the presence of mucus in their baby's stool. In this article, we will delve into the world of baby poop, exploring what mucus means, why it appears, its appearance, and when to talk to your doctor.

What does mucus in baby poop mean?

Mucus in baby poop can be unsettling, but it's not necessarily a cause for alarm. In most cases, it's an indication that your baby's digestive system is working as it should. Mucus is a lubricant that helps stool pass through the intestines. However, in some instances, it can indicate an underlying issue.

Why is there mucus in my baby’s poop?

Milk Allergy

One common reason for mucus in baby poop is a milk allergy. When a baby's immune system reacts to proteins in breast milk or formula, it can lead to excess mucus production. Learn more about milk allergies and what milk allergy poop can look like, and when to bring up concerns with your doctor.


Teething is another factor that can contribute to mucus in baby poop. Babies often drool excessively during this period, which can lead to more mucus in their digestive system.

Infection or illness

Infections and illness can also cause mucus in baby poop because they irritate the intestines and lead to inflammation. The mucus you might be seeing while your little one is sick may indicate that they’re just working through the illness, but keep an eye out for excess mucus, diarrhea, and blood in the stool–these could mean your baby is fighting hard and could use some extra support and guidance from your doctor.

Cystic Fibrosis

While rare, cystic fibrosis can be a serious condition associated with mucus in the lungs, pancreas, and/or digestive tract. A baby with cystic fibrosis may have stools that are especially bulky, smelly, and greasy as their body struggles to properly digest fats. While there is not yet a known cure for cystic fibrosis, there are many ways to manage it, and most children with cystic fibrosis are able to lead normal lives well into adulthood.

What does mucus in baby poop look like?


Mucus in baby poop typically has a slimy or jelly-like texture.


  • Normally mucus is clear, but you might see it take on the color of its surroundings.
  • Newborns produce a black mucus called meconium, which is normal.
  • If you notice green or yellowish mucus, that could indicate their body is fighting an infection or experiencing inflammation in the gut. (Green poop is usually harmless and colored by nutrients in your baby’s diet: learn more about baby poop colors.)

Breastfed babies with mucus in their poop

Breastfed babies often have mucus in their poop, and in general, breastfed babies produce poop that is more “watery” than formula-fed babies. Keep in mind that babies tend to swallow saliva and/or mucus that runs down from their nose while breastfeeding, and this is generally harmless. In some cases, the poop might be indistinguishable from mucus, and this is normal especially in younger babies–the poops tend to become more solid as they get older.

As always, keep an eye out for excessive mucus and indications of blood, and if you see them or have any concerns, don’t hesitate to get in touch with your doctor.

Formula-fed babies with mucus in baby poop

Formula-fed babies may experience mucus in their poop for various reasons, and seeing some mucus doesn’t necessarily indicate an allergy or feeding issue. However, if you recently switched formulas and are seeing excessive mucus, indications of bleeding and/or diarrhea, those could be indicators of a cow’s milk protein allergy, in which case you should consult your doctor about switching to a formula that’s right for your baby.

Do I need to take my baby to the doctor for mucus in their poop?

While mucus in baby poop is often harmless, if you notice excessive mucus, abnormally foul smells, indications of bleeding, diarrhea, or difficulty pooping, it’s a good idea to check in with your doctor.

Explore Enfamil Family Beginnings®

Mucus in baby poop is common. Understanding what it means, why it appears, and when to be concerned can help you stay on top of your baby’s health and well-being as they continue to grow and thrive. Let’s thrive together! Join Enfamil Family Beginnings® to become part of our community of parents and caregivers who have exclusive access to valuable resources, expert advice, and special offers tailored to your baby's needs. Join today for chances to receive free formula samples and a chance to win a year's supply of formula!

All information on Enfamil, including but not limited to information about health, medical conditions, and nutrition, is intended for your general knowledge and is not a substitute for a healthcare professional's medical identification, advice, or management for specific medical conditions. You should seek medical care and consult your doctor or pediatrician for any specific health or nutrition issues. Never disregard professional medical advice or delay seeking medical treatment, care, or help because of information you have read on Enfamil.