Why is Baby Poop Green?

by Dr. Pamela Bandelaria, pediatrician

When your baby is born, they add much joy and excitement to the home.   In the beginning, all they do is eat, nap, cry, and poop, and because they can't communicate, it's essential to know what's expected.  Taking care and cleaning up after your baby poops can be a tricky and messy business, but there are some essential things that you have to know about your baby's poop.

In this article, you will learn about baby’s poop: what normal poop is, what the color and consistency of poop mean, when should you be concerned about your baby’s poop, and when a doctor’s visit is warranted.

What is normal poop?

Each baby is different, and so it stands to reason that their poop will vary too.  No infant will have the same quantity and quality of stool throughout his or her infancy, and no infant will have the same amount and quality of stool compared to other babies. The stool of babies changes in the amount, color, and texture as the immature gastrointestinal tract changes to accommodate the changes in your baby’s feeding and food intake. 

When your baby is born, the contents of the gastrointestinal tract are sterile.  Eventually, bacteria will colonize the bowel. Bacteria is present in the gut to keep it healthy and produce substances needed by the body, such as vitamin K.

The earliest stool a baby produces is a dark-colored, soft, thick, sticky stool called meconium. It is the first kind of stool that your baby passes once they are born. It is dark green to dark brown and has an alarming appearance because it is not the usual kind of stool observed in infants. Meconium is commonly passed within the first two days of life and indicates the viability of the gastrointestinal tract.

As the baby starts to feed, the characteristic meconium turns into brownish-green stools by the third day and becomes yellowish-brown after five days. This transition is expected as there is a natural transition in the color and consistency of the stool when the baby receives breast or formula milk. The consistency also changes from being thick and sticky to curdy and then pasty. It is also normal for those ingesting solid or semi-solid foods such as older infants or toddlers to have soft mashed matter in their stool or find incompletely digested food such as peas or corn. These children may not have chewed their food correctly, and it does not indicate an indigestion problem or gastrointestinal tract.  

Typically, babies poop variably and at different times every day. They can poop as much as seven times a day, and pooping after every feeding is normal. However, some babies do not poop at all in a day. The frequency of bowel movement varies from infant to infant.

What does a baby’s poop color mean?

A baby's poop color can indicate many things about the baby's gastrointestinal function and overall gut health. As mentioned previously, the baby's poop typically follows a transition in color during the first weeks of life. This indicates the gastrointestinal activity of your baby. If your baby follows this pattern, there is usually no cause for concern and means a normal, functioning gastrointestinal tract.

There is not much cause for alarm regarding the color of your baby's stool, but there are certain things in stool that we should watch out for. These include having blood in the stool, having a black stool, or having colorless stools (white-gray or light cream stools), which indicate a lack of bile in the stool. If these are present in your baby, you should bring them to a doctor for medical evaluation.

The presence of black stools may indicate gastrointestinal bleeding. Grayish or pale, white stools indicate a lack of bile products in the stool and may indicate an underlying bile duct or gall bladder problem.  The most common cause of lack of bile leading to white or pale stools is biliary atresia, wherein the bile ducts do not develop in a usual manner leading to bile blockage. This must be evaluated promptly, as it can lead to liver failure and other irreversible and drastic consequences if not adequately addressed.

Why is my baby’s poop green? Is dark green poop normal for babies?

Green poop, especially the dark green kind, is mainly associated with meconium. It is considered meconium when it is passed out within the first two days of life. Meconium is usually made up of the cells of the intestine, mucus, amniotic fluid, bile, and water. The dark color is due to the bile that is also present in the stool. Bile is a fluid produced by the liver and kept in the gall bladder. The primary function of bile is to break down fats so that they can be absorbed and used by the body for energy. Bile is usually circulated through the digestive tract, but some escapes and get passed out with stool. This is what gives the stool its color. It is normal for the baby's stool to be dark green during the first two days of life. As the baby continues to feed, the color and consistency of the stool change.

Is green poop a sign of infection in babies? Is green baby poop normal?

Although dark green poop almost always indicates meconium, it is essential to note that meconium is only passed in the first few days of life. Meconium is a product of the substances ingested by the baby while they were still in your womb. This is a physiologic phenomenon that happens to your newborn baby.  Green poop is normal in the first few days of life, but it will naturally change color as the days progress.

In older infants, especially those already in complementary feeding or eating solid/semi-solid food, typical causes of green poop include intake of iron supplements, eating green foods, or those containing food dye. These should not be a cause of concern if they occur without any other symptoms.

What kind or color of poop is bad for babies?

For infants, normal or good poop is usually brownish to yellowish. It is soft and pasty. Bad poop is generally associated with hard stools and is sometimes watery to oily. It may appear as any color but stained with blood, is foul-smelling, and associated with other conditions such as fever, nausea, vomiting, loss of appetite, and irritability.

Bad poop can be associated with bleeding, which can be seen as black stools that look like tar, indicating a possible upper gastrointestinal bleeding. Bleeding can also be seen when there is a blood-streaked stool, meaning that your baby has lower gastrointestinal bleeding. These may also be due to infection or structural problems along the gastrointestinal tract. Both of these conditions need medical attention to prevent unnecessary blood loss in your baby and to rule out the possibility of other intestinal infections.

Foul-smelling stool or poop that smells different may be due to an infection. Although it is not common for infants to present with intestinal amebiasis, it is still possible if the water used for powdered formula is contaminated. Therefore, it is important to ensure that your baby consumes clean water and that anything your baby takes in is from a trusted source. Proper hygiene and cleanliness are also essential to avoid infection that can lead to these types of stools.

When should I be concerned about green poop? When should I visit the doctor when it comes to my baby’s poop?

As previously mentioned, it is essential to be aware of the natural transition of stools in babies. This will eliminate a lot of unnecessary worry or panic about your baby’s stools. For older infants, if your baby is taking iron supplements or consuming a lot of green food, it can help stop them first and observe if the stool returns to normal. If it does, this means that that particular substance caused the changes in the stool. Knowing this will also ease the worry about your baby’s poop.

If your baby does not have color in their poop, and it remains gray, ashy, pale, or white, or persistently dark green or green-black, it is best to have your baby brought to the clinic for a check-up. This is a sign that your baby might have other underlying problems, and they should be evaluated. This approach is also advised if your baby has green or dark green poop months after birth, or if it reverts back to this color and consistency, or is accompanied by other signs and symptoms. This is because it is most likely that the poop is not meconium anymore and might be caused by something else. If the green poop is associated with fever, diarrhea, irritability, changes in bowel habits, loss of appetite, failure to thrive or weight gain, and dehydration, or if the poop becomes foul-smelling and has blood, these may be signs of infection or other gastrointestinal problems. It is best to conduct an appropriate medical evaluation and administer medical care if warranted.

A baby's poop is usually not much of a concern, but it can give essential clues regarding your baby's gut health and gastrointestinal function and condition. It is necessary to know what is expected and what is not, as it can ease some of the everyday worries and indicates when you should bring your baby to the doctor.