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.
[Sumber: "The Color of the Day: Solving Bowel Movement Mysteries", Dr Jay Gordon & Cheryl Taylor White, CBE]
[Sumber: 'Your Guide tu Baby Stools']