What Your Infant's Poop Says about Their Health

We've got the scoop on poop!
woman changing baby's diaper and plugging her nose

One way or another, what goes in must come out. Yes, I am talking about poop! While typically infants only have a few things going in, what comes out isn’t always as predictable and can leave even well seasoned diaper changers perplexed. What comes out of your infant can be an key indicator of what is going on inside of them, which is why knowing the ins and outs of what is normal or abnormal is important.

So here it is–a list of what you need to know when it comes to your baby’s poop! It’s okay to take a look. (In fact, we recommend it!) 

Good baby poop


Sticky, tar-like, black or green goo is the normal make-up of your newborn’s first bowel movement.

Transitional stool

This should be grainy in consistency and green, yellow, or brown in colour. It typically shows up around day 3-4 following birth. Transitional stool may contain mucus or traces of blood. This is most likely because baby swallowed some of mum’s blood during deliver–so don’t panic!

Breastfed-baby poop

Normal breast milk stools are soft, seedy and/or lumpy and vary in colour, most often being light to mustard yellow or green.

Formula-fed baby poop

Normal formula stools are more formed and vary in colour from light brown, bright yellow, or dark green.

When baby poop goes bad!


Diarrhea in infants is similar to that of adults, meaning that it is soft, watery, and frequent, except that your little one’s stool may be bright green. There are so many possible causes of diarrhea that they are too long to list. Some of the top culprits include: a viral infection, introduction of new foods, reactions to medications, cystic fibrosis, or congenital problems. One thing to keep in mind when searching for a solution to your child’s diarrhea is that, despite it’s inconvenience, it is an effective way for the body to expel the bad stuff! While it can become dangerous if not monitored closely, diarrhea itself is a rather effective and efficient coping mechanism that should not unnecessarily be repressed, unless of course the diarrhea is severe and there is a risk of dehydration and low electrolytes. Keep an eye on your infant’s temperament. If they appear well, then chances are all is good. Trust your instinct if you think something is wrong and always consult your doctor when it comes to diarrhea in young infants, as they can get dehydrated quickly.


Constipation is present when the stools are hard to pass, pellet-like in nature, and may even contain red streaks (fresh blood) if the infant gets tearing at the anus or rectum. Keep in mind that breastfed babies typically have fewer bowel movements as compared to those who are formula fed. Breastfed babies can commonly go a couple of days in a row without having a bowel movement in the first few months. Diaper rash can also cause infants to withhold their bowel movements to avoid the burning and itching that comes with each bowel movement. Keep this in mind and always treat diaper rash as soon as it arises.

More scoop on poop

Food allergies

This should be considered if your baby’s bowel movements are abnormal (constipation or diarrhea). Other signs of food intolerances or allergies include, but are not limited to: inflammation or swelling or any kind, skin changes (most often eczema, hives, or general rashes), itching, chronic runny nose, asthma, vomiting, bedwetting, diarrhea, ear infections, headaches, and change in temperament/irritability.

Cold and flu

Illness in infants is often accompanied by mucousy stools that vary in colour from light yellow to green.  


Iron or iron-fortified foods can cause baby’s stool to darken to a darker green-black.

When to see your doctor

  • Diarrhea that comes and goes for more than two weeks, is increasingly watery, or is persistent for more than 48 hours.
  • Vomiting accompanied by abdominal pain that last more than 24 hours.
  • If your child looks unwell, visibly uncomfortable, is vomiting, refuses to nurse, is lethargic, or shows any signs of dehydration (sunken fontanells, dry mucous membranes, no tears when crying). 
  • If your child appears to be in extreme discomfort while passing stool (soft or hard), has blood in his/her stool, or you find a tear or cut on his/her rectum. (Note: save the bloody diaper–no, seriously! Bring it to your doctor’s appointment.)
  • If constipation is ongoing. Long-term constipation can result from a range of issues such as low fluid intake, food intolerance, allergies, and even thyroid dysfunction–all of which require further investigation and treatment. Possible complications include: obstruction and loss of muscle tone in the digestive tract.

Who knew there was so much information to be gleaned from poop? Paying attention to what their little body's put out is an excellent way for you to understand what the heck is going on inside of them, and will help you feel confident in your knowledge of your baby's health moving forward.