Mucus in Baby Poop: Causes & What to Do

Mucus in Baby Poop: Causes & What to Do

So, mucus in baby poop – is it worth worrying about?

Much of early mamahood involves keeping your eyes glued to everything that enters and exits your baby.

Suddenly, a fair amount of your day is spent researching foods for them to eat, diapers for them to wear, and questions like: what does mucus poop mean in baby?

The good news is Peanut is here to help you answer a bunch of these questions – so let’s get started on the issue of mucus in poop, shall we?

In this article 📝

  • What does it mean when baby poop is mucousy?
  • What does mucus in poop look like?
  • What causes mucus in baby stool?
  • When should I worry about mucus in baby poop?

What does it mean when baby poop is mucousy?

First, a quick spin around the world of baby poop.

Baby poop goes through different stages.

In their first few days of life, your baby produces what is called meconium.

It’s really dark (almost black) in color, pretty sticky, and filled with all the leftovers of what they ingested in the womb.

After that, their stool will turn a greeny-yellow color.

Yep, infant poop can be confusing.

Add mucus to the mix, and it’s hard to know what you’re dealing with.

Suddenly, you’re sending frantic texts to your partner/mom/friend saying “Baby has mucus in poop!”.

Which is really something you never thought you’d have to say, ever.

The thing is, if your baby has mucus in their poop, it may be totally fine. It also may not be.

Your baby’s intestines are working to help move that poop through them.

One way they do this is by secreting mucus to help with the task.

Sometimes, you can see this mucus in your baby’s poop – and there’s no reason for concern.

Other times, it can signal an allergy, infection, or health condition.

How do you tell the difference? Well, it’s not always that easy.

What does mucus in poop look like?

So how do you know if your baby has mucus in their poop?

Well, it can look a little different depending on their age and their diet.

What does mucus in newborn poop look like?

Newborn baby poop is usually darker than older babies, because they’re still processing what they were getting for nutrients in the womb.

So if you see more slimy baby poop from your newborn or green streaks in their darker stool, that’s newborn mucus poop.

What does mucus in breastfed baby poop look like?

Mucus in breastfed baby poop is particularly common since their stool passes through the intestine pretty quickly.

It may look like slimy green streaks that run through the poop and/or a bit like jello.

What does mucus in formula-fed baby poop look like?

Mucus in a formula-fed baby’s stool can look pretty similar to breastfed baby poop, but it’s usually a bit darker, more solid, and a bit smellier.

The key with formula‒fed poop is to look out for green streaks.

What does mucus in toddler poop look like?

By the time they’re toddlers, your child’s poop will be looking pretty similar to adult poops – just smaller.

So while more solid, any toddler mucus poop will have those same tell-tale green slimy streaks.

What causes mucus in baby stool?

Infant poop mucus can simply be the result of drool that has made its way to the other end.

If your baby is teething, they might be particularly drooly at the moment.

Having a cold might mean they have some extra mucus in their system.

But there are some instances when mucus in your baby’s poop is worth paying special attention to.

When should I worry about mucus in baby poop?

There are also some times when mucus can be a sign of something a bit more serious, so it can be worth visiting a doctor if it sticks around for a few days.

Mucus in stool may also be a sign of:

Allergy to animal protein

Also known as allergic colitis, this is when your baby may be allergic to an animal protein that they are ingesting through your milk or through their formula.

If you’re breastfeeding, this doesn’t mean you have to stop – it just may mean that you have to shift to a dairy-free diet.

If you’re using formula, you may have to switch to a more hypoallergenic option.

So what does baby poop with a milk allergy look like?

Well, with a milk allergy, the mucus in baby poop tends to look clearer than the green mucus we mentioned earlier.

It could be undigested milk in baby stool, too, which looks like white or cream-colored “chunks”.


Bacterial and viral infections can both cause diarrhea, as can a change in their diet or yours.

If your baby seems extra fussy, has a fever, or has blood in their stool, it’s definitely worth getting to the doctor.

The big danger with diarrhea in babies is dehydration.

If you notice your baby hasn’t peed in a while, is crying with no tears, or has sunken eyes and a dry mouth, get to the doctor asap.



In some very rare cases, mucousy baby poop can signal a more serious health concern that might affect how your baby takes in nutrients.

This can be caused by conditions such as cystic fibrosis – a genetic condition that can damage the respiratory and digestive systems.

If your baby has cystic fibrosis, they might have trouble putting on weight, have very foul-smelling stools, and thick phlegm.

If you suspect that malabsorption is causing the mucus in your baby’s poop, it’s worth getting to a doctor right away.

In many cases, mucus in baby poop is nothing to worry about.

If your baby has other symptoms, or if the mucus is very heavy and long-lasting, check in with a healthcare professional as soon as you can.

We know this can all be super stressful.

Good luck, mama. We’re rooting for you.

Popular on the blog
Trending in our community