I have often asked parents not to bring poop samples into my office. While there is a lot of information to be gleaned from studying full diapers, I think I can do most stool analysis on the phone or online unless an emergency situation occurs.
There is a wide variety of color and consistency of bowel movements. In my glamorous job as a pediatrician, I discuss this hot topic every day.
A change of pattern can throw the most confident mom for a loop and can even confuse an experienced pediatrician. Babies have blood in their stool fairly often and it virtually never is the sign of serious illness, but I pay a lot of attention to this because it alarms parents and requires that a reason be found.
We shouldn’t be any more surprised to see a variety of bowel movements in our babies than we would in anyone of any other age. In breastfed babies, the mom’s diet can affect the color or consistency of a baby’s stools, particularly if the baby is showing an allergic reaction to a certain food or food group.
Sticky, tar-like and green or black
This is meconium. The first stools of a newborn will be this consistency and color. It is what is present inside the bowels of a newborn upon birth and will clear itself out within the first couple of days and represents the “byproducts” of building an entire human being for nine months.
Greenish or Yellow/Brown, grainy or seedy
This is the transition between meconium and a regular breastfed stool and begins as mom’s milk is coming in on the second, third or fourth day of life. There may be three stools each day, ten, or even twenty. Occasionally, even a baby in the first week of life will skip a day and have no bowel movements at all. Call your doctor to discuss this even though it is normal. This does not require a dietary change or supplementation of a breastfed baby.
Light yellow to bright green, loose/runny, curdy, lumpy, seedy, creamy, mustard-like
These are normal breastfed stools. The consistency, frequency and color vary from day to day. My wife described the smell as “curried yogurt”. Opinions on this odor description differ widely.
Frequent Watery Stool often “Greener” than usual
How can you spot diarrhea in a baby who has loose frequent stools every day? This type of poop is “diarrhea” in a breastfed baby. It can be due to a virus, a bowel infection, stress, anxiety or a food intolerance.
Hard, pellet – like, presence of blood or mucous
This is constipation in a breastfed baby and is so very rare that I cannot recall ever seeing it in a baby who is receiving breastmilk as a sole source of nutrition, as are most babies in the first six months. It could be related to a food allergy. Formula fed babies get constipated much more often and may even have harder bigger stools like older kids and adults. Getting these stools softer is a balancing act of great proportions.
Black stools often accompanied by constipation
This is the result of iron supplementation. Iron fortified infant foods and infant vitamins can cause constipation. A healthy breastfed baby does not need iron supplementation. The iron in breastmilk is much more bioavailable than any other form.
Red streaked stools
This usually comes from bleeding in the lower intestine or rectum. Most often it is caused by rectal fissures which are tiny “cuts” around the circumference of the anus. This can be a reaction to dairy in mom’s diet. Elimination of all dairy is the first line of defense in this situation. I have seen countless babies who had blood in their poop which resolved when mom stopped all dairy products and returned with even a small amount of milk or cheese. Other dietary changes may be needed for breastfeeding moms. Formula fed babies lose blood from the lower intestine when they drink cow milk formula and some have the same losses on soy formula. Occasionally, this “micro-hemorrhaging” can become visible as blood streaking on the surface of the stool. Persistent or increasing blood in the stool or blood mixed with mucus (described as “currant jelly” stool in the texts) requires an immediate call to your doctor.
Green, frothy stools
This can be a result of a hindmilk/foremilk imbalance. A true imbalance is rare. It is often seen accompanying a forceful letdown. Lactation consultants will help moms find a nursing pattern which works to combat this problem. If letdown it too forceful in the early weeks, the solution can be to allow milk to leak into a cloth diaper during letdown, then latch baby back on. Feeding two to three times off the same side may also show improvement. Caution should be used with same side feeding as it can decrease supply.
Green, mucousy stool
This can be a result of a virus. Often the only sign we see of a virus is in the green stool. This is evidence of malabsorption in the intestines. Watch for how many days and with what consistency it is occurring. With a virus, it will run its course over a few days and begin to improve.
Another cause of malabsorption in the intestines can be teething. The profuse saliva of a teething baby can cause irritation in the intestines interfering with proper absorption. When babies teethe, we can see lots of drooling. Large quantities of saliva is swallowed which can irritate the intestines causing runny, acidic stools. This can also cause a rash in the diaper area.
There is something important to point out regarding frequency of stooling in an exclusively breastfed baby. Many parents are concerned when after the early weeks where they may have been seeing a little bowel movement in almost every diaper, they suddenly begin to see days go by without any. This is perfectly normal. There is a great range of frequency of bowel movements with exclusively breastfed infants, ranging from a couple of times a day to several days. There are completely healthy nursing babies that have a bowel movement once a week, once every ten days, or even a few that go a bit longer. If your baby is healthy, developing well, nursing well and the consistency of the bowel movement when it does make its appearance is soft or loose, then do not be concerned. It is not constipation if it arrives in soft form. Constipation would arrive in pellets and hard formed pieces.
In summary, stools in breastfeeding babies are predictably green, brown, yellow or orange. It is runny and has curds almost every time. It changes color with viruses, may have a small amount of blood (call your doc) and may come once a day and even taper off to once a week or more after a few weeks of age. Formula feeding babies may show a little trickier set of changes involving constipation and diarrhea. This is just one small reason to strongly recommend and support breastfeeding your baby.

My daughter who will be 5 months in 5 days has had green and yellow mucus like poop that's really runny and she's had a very bad rash along with it that won't go away i'm constantly changing her diapers and nothings helping! Any suggestions?
If she is a breastfed baby there are two things to consider first: Has there been a change in your diet that coincides with the change in her BMs and rash? Is it possible that she may have gotten a virus that will run its course in 5-7 days?
My 4 week old exclusively breastfed baby has had green, frothy, sometimes tar-like, stools with specks of blood every so often for about a week & a half now.. MD suggested eliminating dairy for 48 hours but i have done that and the poo is still the same.. now what??
It takes up to six weeks for the cow's milk protein to be undetectable in breastmilk. It will begin to lower but may take longer for symptoms to go away.
I was wondering if it is normal for a 9 week old exclusively breast fed baby to poo only only a week. He has been doing this for around 5 weeks now. I think one week he has gone 3 times and one week 2 times. He does not seem to be uncomfortable. He usually goes on Sunday mornings. It is kind of a sour cream consistancy and dark yellow. There is alot of it though when he goes.
It is very normal. If baby is nursing well, wetting well and BM on appearance is soft in form then baby is not constipated. It is not unusual for an exclusively breastfed baby to go one or two weeks inbetween BM's. Dr. Jack Newman speaks of a perfectly healthy breastfed infant that went 30 days. The key is always the consistency of the BM when it does make its appearance.
Ever since my son was born I have to admit that I have been a bit over paranoid about everything. Our son is 2 months old and we have noticed very little streaks of blood along with some mucus substance in his stool; it’s not all the time it’s once in a while. He is exclusively breastfed. I’ve read so many things about oversupply (which my wife has) etc….I don’t know what to think, although we’re going for his 2 month physical on Wednesday. Otherwise he is growing and happy, sometimes fussy and he does cry when he’s tired, but all babies do that. Any suggestions, I want to enjoy this marvelous period, which never will come back with my son and not worry so much.
You might try keeping track of what your wife is eating along with the symptom that you are seeing. You may see a correlation of something or some category that she is eating and the reaction in baby 3-4 hrs. after ingestion.
hi, our foster baby was diagnosed at hospital for being lactose intolerant and put on soy formula. We noticed he was a moderately fussy baby with occasional gassiness but other than that had no problems till his 6 week mark, when I noticed an inch long string of blood in his yellow stool.
We took it to the dr. after a few visits and seeing more blood, they had us go on the Alumentum (sp). Baby has been on it for 3 full days now. Stool immediately became softer and is more green than its previous healthier looking dijon mustard color. Now, every poop has blood mixed in with it. it sort of seems to sit on the surface of the poop…like its getting coated with it on its way out.
It is more than enough to notice. Sometimes you can see flat areas that are the size of a quarter in addition to other tinged areas, sometimes it seems mucousy or tissue-y…
The dr does not seem concerned. He says I should give it 2-3 weeks to 'see'.
its just so unsettling…
Would you happen to have any thoughts on the matter? thank you very much!
Alimentum is dairy based so it doesn’t make sense to diagnose an infant with lactose intolerance and then put them on a dairy based formula. The difference is that the cow’s milk protein is broken down into smaller pieces in this formula, but the protein source is still dairy. Soy if another of the top 7 food allergens and often babies that are allergic to dairy are also allergic to soy. The good news is that many infants can react to dairy prior to the age when their gut closes (approx 6 months) because the protein goes directly into the blood system with an open gut. Once that gut closes we sometimes see the reactions stop. This is more commonly caused a sensitivity instead of a true allergy.