Baby Poo: The Ultimate Guide

Baby poo is probably something you were expecting to deal with as a parent, but did anyone tell you how varied the contents of your newborn’s nappies could be? Runny or firm, light or dark, green, black or yellow, your baby’s poo can come in many different colours, shades and textures. Those nappy changes are a big part of any parent’s daily routine, but they can also be an important way of keeping an eye on your baby’s health. Learn what the colour, consistency and frequency of your baby’s poo can reveal about your little one’s health and development.

Your Baby’s Poo — What’s Normal?

You might be wondering what healthy baby poo should look like. It’s a fair question, because the colour and consistency of your baby’s poo changes over time depending on various things, especially what your baby is eating. Here’s a rough guide to what you’re likely to find in your little one’s nappies over the first few days, weeks and months after your baby’s birth.


Your baby’s first few nappies will probably contain a gooey, dark-green, tar-like substance, with hardly any smell. This is called meconium. This special kind of poo is made of things like the skin cells and other particles your baby swallowed along with the amniotic fluid while still inside your uterus. It takes a few days for all the meconium to pass out of your newborn’s system, but as this happens your baby’s poo will get lighter and runnier. Shifting from almost black to a yellowy green with less mucus present. Regardless of whether you’re breastfeeding or using formula, giving your baby colostrum (your very first, nutrient-rich breast milk) for the first few feeds can speed up the passage of meconium. Tell your midwife or doctor if your baby’s first bowel movement doesn’t happen within the first 24 hours after birth.

Regular Baby Poo

Once the meconium is out of your baby’s system, regular poo can vary a lot, depending on how you’re feeding him or her. Here’s a brief guide to what your little one’s nappies could hold in store for you:

  • If you’re breastfeeding your baby. In the first few months your baby’s stools may look a little like mustard, with a slightly runny and sometimes grainy consistency. The poo will have no smell.

  • If you’re feeding your baby with formula. The poo of a formula-fed baby will usually be firmer and smellier than that of a breastfed baby. It also tends to be darker in colour – formula-fed baby poo can be pale brown or may even take on a yellowy-green hue.

  • If your baby’s in the weaning stage. When you start introducing solid foods, at around 6 months, you’ll start to see (and smell!) some major changes in the contents of your baby’s nappies. His or her stools will get firmer and darker, and they can smell a bit stronger now too.

If your little one is eating finger foods, you may notice some undigested bits of food like the skins of peas or tomatoes. There’s no need to worry – this is entirely normal. You baby’s digestive system is still learning how to process all these new foods.

In Summary

Your baby’s first poos after birth will resemble black tar and will contain particles they swallowed along with amniotic fluid inside the womb. It’s common to find mucus in baby poo at this stage and as it starts to take on a more regular brownish look. However, you may notice a few differences: If you breastfeed your baby, the poo may look a little like mustard and be slightly runny. If you feed with formula, the poo will be slightly darker with a pale brown colour. After you begin introducing solid foods, the way the poo looks may vary depending on what your baby eats.


Yellow, Green, Black, Red — What the Colours of Baby Poo Can Mean

You might be surprised by a change in the colour of your baby’s poo, which can range from the mustard hues of breast-milk poo and the darker tan of formula-fed baby poo to various other shades of yellow, brown or even green. You may also notice mucus in baby poo, which can create a translucent or milky colour. Green poo, in particular, can be alarming the first time you see it, but it’s usually harmless. All sorts of things can cause it, including some types of infant formula. It may be the result of certain medicines or green foods passed on to your baby through breast milk. As long as your baby seems happy and well, with no change in his or her patterns of behaviour, sleeping or feeding, then green poo probably isn’t any cause for concern. Check in with your doctor or health visitor if you notice other symptoms alongside the green poo.

Warning Colours

Certain colours of stool can be a sign of a possible health issue. Always check in with your doctor if your baby’s poo is:

  • Red. Traces of red can be due to blood in your baby’s faeces, so it’s important for your baby’s doctor to look into what might be causing it. Keep in mind, though, that there are plenty of harmless reasons for red poo. Babies can sometimes swallow a little blood during delivery. If your little one is eating solids, certain foods, especially beetroot, can also give poo a red tint.

  • Black. A black stool could, in some cases, be caused by blood coming from the stomach or gut, but again certain foods – blueberries, for example – could also be to blame. It's important to know that very dark green poo can sometimes appear black. Green baby poo — even a dark shade of the colour — is usually nothing to worry about. Your baby’s first poo – meconium – can also look black, and this isn’t a problem either.

  • White or pale. Very pale or white stools are very rare, but if you see poo this colour in your baby’s nappy, call your doctor, as it could be a sign of a liver condition that needs treatment.

Baby Poo Colour Chart

This handy chart and table below can help you visualise the array of baby poo colours, what’s typical and when to contact your baby’s doctor:

Baby Poo ColourBaby’s DietIs it normal?
Very dark greenFormula or breastfedThis poo (or meconium) is normal in your baby’s first few days. It may also appear black.
Mustard yellowBreastfedNormal
Dark tanFormula-fedNormal
GreenFormula or breastfedCertain types of formula can cause green poo, or certain medicines or green foods that are passed to your baby through breastfeeding.
BrownAny dietNormal – especially for babies on solids
BlackFormula or breastfedSometimes dark green poo may look black – especially in your baby’s first few days (meconium).
RedAny dietCertain solid foods may cause red poo (e.g., beetroot).
It may also be due to blood in the poo, so contact your baby’s doctor for more advice.
White or paleAny dietThis colour is rare but may be a sign of liver disease, so contact your baby’s doctor.


In Summary

Baby poo can come in a variety of colours. Some colours are quite normal, including green and everything from yellow to brown. However, certain colours can be warning signs: red, black, white, or grey. In some cases, red-coloured and very dark green almost black-coloured poo could be from food sources or pass through your breast milk. Contact your doctor if you think your baby’s poo is a colour that can’t be traced back to a food.


How Often Should Your Baby Poo?

How often your baby fills a nappy can differ a lot, depending on his or her age and on what method you use for feeding your baby.

If You’re Breastfeeding

In the first few weeks a breastfed baby may poo several times a day, sometimes as often as after every feed. After around six weeks the frequency of bowel movements will decrease. In fact, sometimes your little one may even go several days without filling a nappy. As long as the stools are soft – and your baby is feeding well and not showing any signs of discomfort or restlessness – infrequent poos don’t usually mean your baby is constipated.

If You’re Formula Feeding

If your baby is getting all or most of his or her daily nutrition from formula, you might see up to five full nappies a day in the first few weeks. This usually decreases steadily after that, to about once a day after a few months. If you’re ever concerned about how many poos your baby is doing, speak to your midwife, doctor or health visitor.

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Watery Poo – How to Recognise and Deal With Diarrhoea

The colour, frequency and consistency of your baby’s poo can vary. As long as your child’s weight gain and growth are on track, and the stools are soft, things are probably fine. Keep in mind, that it’s not unusual for breastfed babies to pass looser stools. However, if your baby’s poo seems watery, especially if those bowel movements suddenly start coming more frequently, your little one may have diarrhoea. Watery poo accompanied by a fever and foul-smelling nappies is likely to be a sign of a stomach infection. Always let your doctor know if you suspect your baby has diarrhoea, and make sure that he or she gets enough fluids in the meantime, because babies have a higher risk of dehydration. If your baby is still exclusively breast or bottle fed, you can do this by keeping on breastfeeding or giving your baby formula. It may help to give smaller quantities but more frequently than usual. If your little one is eating solid foods or a combination of solids and breast milk or formula, try giving extra sips of water regularly.


Newborn Care
Meconium: Your Baby’s First Poo

How to Recognise Dehydration and What to Do About it

It’s quite easy for babies to get dehydrated, and when this happens it needs to be treated urgently. As long as your baby gets prompt treatment he or she will usually be OK, so call your doctor or visit your local A&E immediately if your infant shows any of these signs of dehydration:

  • Fast breathing

  • Few or no tears when crying

  • Dry mouth

  • Sunken fontanelle (the soft spot on top of his or her head)

  • Dark yellow pee

  • No pee in the last 12 hours

  • Cold, blotchy feet and hands.

When There’s No Poo — Constipation

With all the variation in how often your baby poos – from several times a day to once or twice a week – you may sometimes wonder how you can tell if your little one is constipated. Constipation is more common after the introduction of solids, but it can occur in younger babies, too. Here are some typical signs that your baby might have constipation:

  • Fewer than three poos a week

  • Difficulty passing a stool

  • Bigger stools than usual

  • Hard, dry, lumpy or pellet-like poo

  • If your baby has an unusually firm tummy

  • Loss of appetite

  • Poo and wind that’s smellier than usual.

What Can You Do About Constipation?

There are some things you can do to try and get things moving again. Lying your baby down and gently moving his or her legs in a cycling motion may help. A gentle tummy massage could also ease some of the pressure. Here are other tips for managing constipation:

  • If your baby is still exclusively breastfed or formula-fed, you could give your baby small amounts (30 to 40 millilitres) of water that’s been boiled and then cooled back down again

  • If your baby is eating solids, check that he or she is getting enough fibre. Prunes, apple and pears are great for constipation.

  • Don’t give your baby prune juice, especially if he or she is younger than nine months.

  • Don’t add anything to formula, such as sugar, malt extract or rice cereal. Apart from being ineffective, anything solid that you put into formula could create a choking hazard.

  • If you don’t see any improvement in a day or two, talk to your doctor or health visitor. In some cases, your doctor may prescribe a laxative or examine your baby to rule out any underlying medical condition.

How to Tell if Your Baby Has Done a Poo

Your little one’s poo may not always be particularly smelly, particularly when they are a newborn. So how can you tell when it’s time to change the nappy? Straining is a tell-tale sign. Small babies often struggle to pass a stool, so you may notice your baby getting a little red in the face when trying to push out their poo. Over time, you’ll learn to recognise your baby’s facial expression when they’re passing a stool.


If you’re unsure whether there’s anything in your baby’s nappy, take a peek inside without removing it. Gently pull out the waistband on the back and to quickly look inside. If your baby’s nappies are the right size and fit, the waistband will return to its original position when you carefully release it.



Your baby may experience watery poo from time to time, particularly if they are breastfed. However, if the watery poo is accompanied by a bad odour, a fever and happens often, they may be suffering from diarrhoea. Always let your doctor know if you suspect your baby has diarrhoea, and make sure that he or she gets enough fluids in the meantime as babies are more at risk of dehydration.

The Bottom Line

You might not have realised until now just how much there is to know about your baby’s poo, but don’t worry: There’s no need to go over every single dirty nappy with a magnifying glass! Once you get used to your child’s bowel movement patterns, and their usual colour and texture, you’ll probably notice any changes pretty quickly. If you’re ever unsure or worried about anything you find in your little one’s nappy, your midwife, health visitor or doctor are there to help advise you and answer any of your specific questions.

How we wrote this article
The information in this article is based on the expert advice found in trusted medical and government sources, such as the National Health Service (NHS). You can find a full list of sources used for this article below. The content on this page should not replace professional medical advice. Always consult medical professionals for full diagnosis and treatment.

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