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Should my Breastfed Baby Poo every day or is Breast Milk all used up?

I've been thinking of writing a blog on breastfed babies and poo for a while now. Mainly because I seem to be posting in breastfeeding support forums and saying the same thing over and over. A mum posts her concern that her breastfed baby hasn't pooed for several days. Then lots of people reassure her that it's ok because breastmilk is all used up / there is very little waste / it's perfectly normal for a breastfed baby to have 10 days between bowel movements. So today I want to talk a bit about frequency of bowel movements for a breastfed baby - and this idea that milk is all used up.

What's a normal frequency

"Let's start at the very beginning - a very good place to start," as they sing in the Sound of Music. When a baby is born their bowel is full of meconium, a sticky tar like substance which is made of all the things that the baby has ingested in the uterus (amniotic fluid, lanugo and substances from the gut itself, like epithelial cells, bile etc). A baby should start to move their bowels within the first 24 hrs to pass meconium. One of the things which colostrum does at this stage is to act as a laxative to help clear out the colostrum, so a good sign of colostrum going into baby is that the meconium is moving out. A newborn should be moving their bowels every day.

Within a few days (2-4 days usually) mums experience "milk coming in", technically known as secretory activation or sometimes referred to as the onset of copius milk production. Once this happens and the baby is getting much larger amounts of milk there are much more frequent poos - several a day. Often young babies will poo at every breastfeed. This is normal and again is a good sign of milk intake and good breastfeeding.

In the early weeks a baby absolutely should be pooing EVERY day, and if a young baby is not pooing every day then feeding should be evaluated to see if baby is taking in enough milk, and to ensure there are no medical issues which might prevent stooling.

Image licensed under creative commons from

Image licensed under creative commons from

Slowing down

At around 6 weeks poo frequency does slow down. The Wonder Weeks book discusses a change in metabolism around 5 weeks which I suspect may be related to the change in frequency - but I've been unable to track down the research yet which gives more detail on the metabolism change (if you know of it, please send it my way). Some babies do continue to poo at every feed for some time yet, the majority of babies slow down but continue to poo each day (usually still more than once), but some start to have days between stooling at this stage. Some babies may only have a day or 2 between poos, some babies might only poo weekly, some might be as long as 10-15 days. A French study (Courdent et al 2014) discusses a baby who had 28 days between stooling! The weekly or 10 day pattern may be described as normal by your Health Visitor or GP and indeed it is considered statistically normal, however there are many things which may be considered statistically normal in our society which may not necessarily be physiologically normal. If I take an example of allergy - a presentation to UK parliament in 2004 found that 45 % of adults had suffered from eczema, hayfever or asthma in the previous year. Something affecting almost half of the adult population could well be considered statisically normal, but allergy is certainly not physiologically normal. So could it be that infrequent stooling is not really normal?

Breastmilk leaves no waste?

I find that most mothers do wonder whether it could be normal when there is a change from frequent to infrequent stooling. When they ask about this however, they are given this information about breastmilk having little or no waste. So let's examine that shall we? Could breastmilk be all used up? What are the components of breastmilk which might be left over in poo?

Breastmilk contains far too many components for us to discuss them all, and we still don't know everything that is in breastmilk. We can look what makes up the largest volumes in breastmilk though. The most abundant constituent of breastmilk is water. Breastmilk is almost 90% water. So that one has some logic as excess water is excreted in urine. Saying that though - mild dehydration is obviously a cause of infrequent stooling, and a baby who is not drinking enough will have infrequent stooling. The next most abundant component are the sugars. Within the milk sugars are lactose, and special milk sugars called Human Milk Oligosaccharides (HMOs). HMOs make up the 3rd most abundant element in breastmilk, and guess what - babies cannot digest HMOs. HMOs appear to be solely in milk in order to facilitate bacteria in the gut. In their 2012 paper on HMOs Marcobal and Sonnenburg state:

Human milk oligosaccharides (HMO) constitute the third most abundant class of molecules in breast milk. Since infants lack the enzymes required for milk glycan digestion, this group of carbohydrates passes undigested to the lower part of the intestinal tract, where they can be consumed by specific members of the infant gut microbiota.

A paper from Jantscher-Krenn and Bode also in 2012 looking at HMOs states:

HMO have long been regarded as metabolically "inert" to the host, as significant amounts are excreted with the fe-ces. HMO reach the colon intact where their prebiotic effects promote healthy gut colonization. HMO can also function as soluble decoy receptors and block adhesion of microbial pathogens to epithelial surfaces.

So we know that babies can't digest the HMOs. They pass right to the colon where they affect the type of bacteria which colonise the area and significant amounts are excreted in faeces, i.e. not used up. A second function is "decoy receptors". This means that in the GI tract they physically attach themselves to pathogenic bacteria species and they take those pathogenic species out of the baby's body via the faeces. This is a fantastic method of clearing out pathogens, another of breastmilk's amazing properties, and it is done via the faeces. So HMOs pass in the poo, and they take bacteria out with them. Poo contains billions of bacteria, good and bad species, and the bacteria is not "all used up" by the baby.

What other components are in poo? Well there are old cells which slough off from the intestinal lining. There is bile, old blood cells etc. Poo would be white if bile wasn't present - and this is one of the reasons that HCPs ask about the colour of your baby's poo. There will also be some mucus. Mucus is made in the intestinal walls to lubricate the passing contents. Usually the mucus is in small quantities so isn't really noticeable in your baby's nappy, but it is present in the poo (and isn't used up). Large quantities of mucus (like globs of jelly or long strings) can be signs of intestinal irritation however.

Setting aside this information about waste produced in a breastfed baby, there are 2 other points I think it's important to consider if you are told that there is no or little waste with breastmilk:

  • Babies who are pooing infrequently tend to have a massive "poosplosion" when they do finally poo, or they may fill several nappies in succession. This completely flies in the face of the argument that the breastmilk was used up. If it was used up then where did this large amount of poo come from? What it does suggest is that the poo was actually sitting in the bowel for several days and simply wasn't moving out.
  • Most breastfed babies are still pooing daily after 6 weeks. If breastmilk is all used up, then how could this be the case? How could some babies drinking breastmilk be creating waste and others are not?

As long as its soft it's not constipation?

Parents are usually told that its not constipation if the stool is soft. Consistency may be a good indicator for adults, maybe even for formula fed babies - but does this apply to breastfed babies?

A study looking at the effect of sugars on infant's stool characteristics (Scholtens et al 2014) states the following about HMOs:

First, an increase in microbial mass due to the fermentation of the oligosaccharides can increase the faecal water content, which can results in softer stools. Second, the selective fermentation and growth of Lactobacillus species and bifidobacteria[19,20] and the subsequent production of SCFA can increase the water content of the faecal mass..... Third, as HMO are specific types of dietary fiber, they can be hypothesized to bind water and thereby increase the water content of the faecal mass

So regardless of how long the poo sits in the bowel, breastmilk poo is likely to stay soft as water is increased due to the fermentation. Anyone who has experimented with fermenting foods or creating a sourdough starter for bread will understand this principle. As the poo (full of fermentable HMOs) continues to sit in the bowel (full of fermenting bacteria) it is reasonable to assume, I think, that fermentation continues and water continues to be increase in the faecal contents.

Is it a Big Deal if a Baby Skips Days?

We know it's common. One French study (Courdent et al 2014) found that 37% of breastfed infants experienced at least one episode of infrequent stools (infrequent stools was defined as greater than 24hours between stools) over the first 34 weeks. This is where I feel it's important to distinguish the difference between a baby who is having a few episodes here and there over the first few months where they miss a day or 2 between poos, and the baby who develops a consistent pattern of weekly stooling. Babies who are teething may have a temporary change and miss a day or two and then return to daily stooling. Illness, change of environment (maybe a holiday/ move of house), change of daily rhythm etc can all play a role, and temporary changes are to be expected. That is a very different picture to consistent weekly stooling, or every 10 days. In the book "Baby Poop: What Your Paediatrician May Not Tell You", Linda Palmer states the following:

some exclusively breastfed babies will go 7 to 10 days, and dare I say even 17 days between poops, without having hard or painful stools. This is common enough that most doctors call it normal. In my experience, any such baby I've worked with has had some other issues going on and has benefitted from working through these issues. You may like to think of it like constipation, in terms of searching for causes, especially when it regularly goes beyond 3 days

Causes and How to Encourage Frequency

Causes of infrequent stooling (greater than 24 hours) in breastfed babies is wide and varied, and working with an IBCLC (International Board Certified Lactation Consultant) through the possible causes is the best idea to establish what might be happening with any individual baby. Here I'm just going to mention a few common reasons and what you can do to encourage a daily rhythm again:

1. Not enough milk

This is a really common cause of infrequent stooling, and is the reason that weighing is useful in the early days. If there isn't enough "raw material" going in, then there really wont be very much waste, but nor will there be good growth. See the previous blog on low weight gain for ways to increase milk intake and circumstances where feeding on demand is not enough.

2. Teething / Illness / Temporary Upsets

The word disease comes from the idea of dis-ease. There are lots of things which disrupt the normal ease in our bodies, and it is very common for these to disrupt stooling pattern. Teething babies can have a bit of inflammation going on for example. They can swallow mucous, have a fever etc which will affect normal gut function. Colds and bugs are similar. Generally these are short lived and the baby returns to their daily pattern in a few days. Tummy massage and frequent feeding can help baby with the discomfort of whatever is going on and help to move the bowels.

3. Antibiotics / Temporary Lactose Intolerance / Tummy bug

Antibiotics don't just kill off pathogens. They destroy populations of our good bacteria too including those lining the walls of the gut and in doing so the border cells can be temporarily damaged. This damage to border cells also happens with a GI bug. When this happens the baby produces lactase less effectively and doesn't digest lactose as efficiently (known as temporary lactose intolerance and discussed in more detail in this previous blog on Food Sensitivities. This means that more lactose passes into the lower intestine undigested in the same way as the HMOs. This can cause diarrhoea or conversely it can produce more infrequent stools and more gas. An article by Lomer et al in 2007 in Alimentary Pharmacology and Therapeutics says the following:

The typical symptoms of lactose intolerance include abdominal pain, bloating, flatus, diarrhoea, borborygmi, and on some occasions, nausea and vomiting. In a few cases, gastrointestinal motility is decreased and subjects can present with constipation possibly as a consequence of methane production. Animal models have shown a marked reduction in the major migratory complexes of the gut when infused with methane, slowing gut transit

Many mums and babies can be exposed to antibiotics during birth or in the early weeks due to something like mastitis.

This brings me on to the rotavirus vaccine. Some people find that their baby seems to change to a more infrequent pooing pattern after the rotavirus vaccination. I have not been able to find any information on this in the patient information leaflets, but having a trawl through the research I found that lactase production is also reduced with infection by rotavirus, and indeed the site lists temporary lactose intolerance as a potential side effect of the vaccination.

Where temporary lactose intolerance is a cause of infrequent stooling, tummy massage again can be very helpful with relieving gas and moving the bowels. Some dyads also find probiotics to be helpful (which would be another blog in itself). I am also linking in the further reading section an article which give stats on how breastfeeding protects against rotavirus diarrhoea.

4. Medications / Supplements

These can also play a role, in the same way that they can affect the gastric motility in adults. A large number of babies are now being medicated for reflux. Many parents find that alginates (e.g. gaviscon) can cause constipation. Alginates may also reduce appetite and therefore milk intake. Second line treatments for reflux can affect the microbiome and that may also affect gut function. Again tummy massage is helpful, probiotics may also be helpful but ultimately getting to the root cause of the reflux and resolving so that medication is not needed is the ideal route in my view. See part 1 and part 2 of my blogs on reflux for more details.

Supplemental iron in mum's diet can also cause constipation in her breastfed baby.

5. Oversupply / Expressing

In number 3 I talked about the effect of too little lactase. A mum who is in oversupply or who is expressing a lot of milk on top of feeding her baby may find that at times her baby is simply a little overwhelmed by lactose in her milk. As I have mentioned in previous blogs many mums worry about oversupply when they actually have a completely normal supply, and I am certainly not suggesting that babies should stay on one side so they don't get too much foremilk! The result of that is frequently that babies don't get enough milk and we are back to cause number 1 (See previous blog on foremilk and hindmilk).

Some mums who are expressing regularly for a freezer stash can also find that their baby is unsettled, gassy and may have infrequent stooling. (See previous blog on potential problems with the freezer stash).

6. Microbiome

We've mentioned bacteria a few times above. Our gut is teeming with bacteria and many of them are essential to good gut function. Functional constipation, which is constipation with seemingly no organic cause, is linked to an dysfunctional microbiome. We inherit our microbiome from our mothers ideally through a vaginal birth, then through skin to skin with family members, through our home environment, through the bacteria in breastmilk etc. For very many of us however, things don't go exactly to plan. Babies born by C-section will have a slighlty different colonisation, those born in hospital have different colonisation to those at home. Some babies spend time in hospital, and mothers will have different bacterial species in their milk depending on their diet and how that affects the species in her gut. Add in antibiotics, and chlorinated water and our obsession as a culture with killing germs and our gut microbiome is often not what it should be. Where the microbiome is affecting gut motility and stooling pattern probiotics may be helpful.

Interestingly the microbiome has also been associated with colic in many studies and the Baby Poop book quotes a study which found a higher percentage of colic in babies with infrequent stooling than in babies with daily stooling.

7. Food Sensitivities

A common reason for infrequent stooling is food sensitivities - either food intolerances or allergy, and food sensitivities are increasing rapidly in the population in the last couple of decades. I discussed this in a previous blog on Breastfeeding and Food Sensitivities.

Food can also be a resolution to infrequent stooling. The French study I mentioned above found a dietary influence, stating, " The most frequent action for infants was abdominal massage (79%), whereas in mothers it was consumption of fruit juice/mineral water rich in magnesium/vegetables"

Notice that it was the mother who consumed the fruit juice - not the baby! I unfortunately still hear stories of fruit juice being recommended to babies under 8 weeks to aid with frequent stooling. Babies of this age should be receiving breastmilk exclusively.

So is it anything to worry about?

Skipping days is statistically common, and although it's usually nothing to panic about, it is, however, a sign that gut motility is a little sluggish and the gut function isn't working quite as well as it could be. In most cases that I have worked with, small changes do get babies back into a more frequent pattern of pooing, further contradicting the idea that breastmilk is all used up. For most babies the resolution is optimising breastfeeding, daily tummy massage (The I Love You infant massage is particularly effective I find), removal of any allergens and often supporting the gut microbiome. It might not be a big problem, but personally I prefer to see babies pooing regularly.


If you have any questions about a consultation or would like to arrange to meet, please get in touch.

Further Reading

1. Allergy Burden in the UK:
2. Courdent M1, Beghin L, Akré J, Turck D Infrequent stools in exclusively breastfed infants. Breastfeed Med. 2014 Nov;9(9):442-5. doi: 10.1089/bfm.2014.0050. Epub 2014 Sep 22.
3. A. Marcobal, J. L. Sonnenburg 2013 Human milk oligosaccharide consumption by intestinal microbiota Clin Microbiol Infect. 2012 Jul; 18(0 4): 12–15.
4. Jantscher-Krenn E1, Bode L. Human milk oligosaccharides and their potential benefits for the breast-fed neonate. Minerva Pediatr. 2012 Feb;64(1):83-99.
5. Petra AMJ Scholtens, Dominique AM Goossens, and Annamaria Staiano Stool characteristics of infants receiving short-chain galacto-oligosaccharides and long-chain fructo-oligosaccharides: A review World J Gastroenterol. 2014 Oct 7; 20(37): 13446–13452.(
6. Lomer, Parkes, Sanderson Review article: lactose intolerance in clinical practice – myths and realities. J. Alimentary Pharmacology and Therapeutics Volume 27, Issue 2 January 2008 Pages 93–103
7. Ramig. Pathogenesis of Intestinal and Systemic Rotavirus Infection J Virol. 2004 Oct; 78(19): 10213–10220.
8. Isabelle Beau,1,2 Jacqueline Cotte-Laffitte,1,2 Monique Géniteau-Legendre,1,2 Mary K. Estes3 and Alain L. Servin. An NSP4-dependant mechanism by which rotavirus impairs lactase enzymatic activity in brush border of human enterocyte-like Caco-2 cells. Cellular Microbiology (2007) 9(9), 2254–2266
10. Chang Hwan Choi* and Sae Kyung Chang Alteration of Gut Microbiota and Efficacy of Probiotics in Functional Constipation J Neurogastroenterol Motil. 2015 Jan; 21(1): 4–7.(
11. Dubois NE, Gregory KE Characterizing the Intestinal Microbiome in Infantile Colic: Findings Based on an Integrative Review of the Literature. Biol Res Nurs. 2016 May;18(3):307-15.
12. Rotavirus vaccination vs breastfeeding reduction:

About the author

Carol Smyth

I am an IBCLC (International Board Certified Lactation Consultant) in private practice in Northern Ireland and a La Leche League Leader with La Leche League of Ireland

Important Information

All material on this website is provided for educational purposes only. Online information cannot replace an in-person consultation with a qualified, independent International Board Certified Lactation Consultant (IBCLC) or your health care provider. If you are concerned about your health, or that of your child, consult with your health care provider regarding the advisability of any opinions or recommendations with respect to your individual situation.