Your baby's bowel movements change significantly during the first year of life. This is because the composition of the stool is related to your baby's development and their changing diet: breast milk or pre-formula, follow-on formula, and later porridge, fruit and vegetable purées, as well as other solid foods.

In general, babies' diaper contents consist of a mixture of live and dead bacteria, undigested food particles, connective tissue and muscle fibers, and approximately 75% water. 

Hard as a stone, soft as butter, or runny like yogurt. A baby's stool can be any of these. Generally, breastfed babies may have mustard-yellow, slightly mushy, or completely smooth stools: the so-called breastmilk stool (short: milk stool). In babies fed with formula, the stool is more likely to have the consistency of pudding. With the introduction of solid foods, the consistency changes, and the very soft milk stool gives way to increasingly firmer stools. 

The amount and frequency can also vary greatly. So there’s no need to worry if you have to wait a few days for a bowel movement! Anything from several times a day to just once a week, or even less frequently, is completely normal—as long as your baby continues to gain weight.

The stools of exclusively breastfed babies often have hardly any smell, at most a slightly sweet one, while the stools of bottle-fed babies can occasionally smell somewhat unpleasant. However, the smell only becomes really unpleasant when your baby comes into contact with different protein sources from mixed feeding and especially with meat. The activity of bacteria in the gut, which produce a lot of substances and gases, is the cause of the smell. In addition, stools that remain in the gut for longer have an even more unpleasant odor than those that pass through the gut quickly.

The color of the stool also changes regularly. From black, right after birth, to light green, mustard yellow, and then brownish during the weaning phase. Babies who drink breast milk consume a variety of proteins every day through the nursing mother's diet. Depending on the proteins, the color of the stool can also change.

But this does not mean that the stool of babies who exclusively receive baby formula always has the same color. Because the gut flora (the composition of bacteria in the gut) changes significantly during infancy, and thus the color of the stool also changes in non-breastfed babies.

Pssst…. In August 2022, Stiftung Warentest named us the test winner among 21 tested pre-formulas. 

Now then, let's take a closer look. We have divided a baby's bowel movements into different categories, paying particular attention to the color.

In the first few days after birth, your baby’s stool is a bit unusual. More precisely, it consists of thickened bile, hair, and skin cells that your baby swallowed in the womb. The stool is dark green to pitch black. It also has no odor and is quite sticky and tar-like in consistency. As mentioned, it’s something a bit unusual.

After the meconium, the color of the stool changes from dark green to a lighter green. A sign that not only colostrum, but colostrum mixed with milk is being digested. Gradually, the excretion through the anus develops into proper stool.

Exclusively breastfed babies usually have mustard-yellow stools. The consistency is soft to runny. The smell is rather mild and slightly sweet. Definitely no perfume, and yes, even baby poop can be really gross, especially when it flies through the air and then sticks to the wall opposite the changing table! But it still doesn't really remind you of "real" poop. In terms of timing, almost everything is normal: from several times a day (especially at the beginning) to sometimes only once a week or even less frequently.

Stool when consuming infant formula is dark yellow, more of an ochre yellow, and can also turn greenish-brown. The consistency is rather mushy and soft, comparable to pudding or creamy peanut butter (without chunks). The smell is stronger than with breast milk stool. This is because when consuming infant formula, certain bacteria can enter the intestines through the bottle, which causes the smell. Defecation occurs less frequently, but the volume is greater.

With the introduction of solid foods, the color of the stool generally becomes darker. However, different colors may appear depending on the meal. The consistency will become increasingly firmer, but at first, it won't be consistently hard either. You may also find undigested pieces of vegetables, fruit, or meat in the stool. So don't panic if you see undigested blueberries and grapes or stringy banana remains. The bowel needs time to gradually adjust to the new situation. Just a quick word about the smell: it is definitely stronger than before.

Green stools can have various causes. Stressed babies may occasionally pass green stools. Regular baby formula could also be the reason. However, the green color is usually due to your baby having eaten more than usual, or, if you are breastfeeding, to you having had a generous portion of spinach or other green food for lunch. Or perhaps there was spinach and broccoli in the baby food?

A few red discolorations in the stool are no big deal. They may be related to minor injuries to the baby's anus or to your baby swallowing blood from a cracked nipple. A distinct redness, on the other hand, is a sign that may indicate health problems. In this case, please contact your pediatrician.

A noticeably pale color of the stool also points to possible illness-related causes. In this case, please also contact your pediatrician.

Clay-colored stools in babies can indicate problems with the liver or gallbladder. Possible reasons for this are restricted production of or flow of bile. So, if you notice clay-colored stools in your baby, go to the pediatrician. They can determine the exact cause.

Changes in the contents of the diaper, as well as different colors and odors, are therefore by no means a cause for concern. As a general rule: If your baby is not fussy, is not in pain, is gaining weight appropriately, their stool is soft, and no straining is necessary, then you do not need to worry.

• In the event of diarrhea (more than five times a day, watery – liquid, unpleasant odor),

• constipation (less frequent bowel movements, very hard, sometimes ball-shaped consistency, and straining),

• a pungent odor and/or frothy consistency,

• green color for more than one day,

• blood in the stool or whitish stool

it is worth contacting a midwife or a medically or pharmaceutically trained professional.

A baby's stool is an endless topic for parents. This is because stool is, among other things, an indicator of your baby's health. If something is wrong with the stool, it could be due to the baby food or other factors. If your baby receives breast milk or alternatively baby formula enriched with GOS, the good bacteria in the intestinal flora are supported in the digestion or further processing of food.

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