Baby poop

Parents are often surprised by the contents of their baby’s diaper. It’s not uncommon for them to have questions about the colour, texture, and frequency of their little one’s bowel movements. This is normal, as the characteristics of a baby’s poop change over time.

Colour

During the first few days, a newborn’s poop is a very dark green or black. This is because they’re eliminating a substance known as meconium, the waste that accumulated in their intestines while they were in the womb. Meconium can include amniotic fluid, dead cells, and intestinal secretions. Meconium is eliminated within 24 to 48 hours after birth.

The first form of breast milk produced immediately after birth (colostrum) acts as a laxative for the newborn, helping to clean out their digestive system. Thus, during the first week of life, the colour of a baby’s poop will be different shades of green as they expel all of the meconium, and then gradually become a mustard yellow.

If they are breastfed, it will range from mustard yellow to yellow-green. The stool of a baby who is bottle-fed with formula will be more green or brown in tone (e.g., forest green, khaki green, lime green).

When a baby starts eating solid foods, the colour of their poop will change depending on what they eat. For example, it might be orange if they eat a lot of carrots or purplish red if they eat beets. However, it will most often be brown.

Texture and smell

The meconium a baby eliminates during the first few days has a very sticky texture similar to tar or molasses. While it’s not always easy to clean up, it indicates that your newborn’s intestines are functioning as they should. The good news is that it isn’t very smelly!

What are the differences between a breastfed and a formula-fed baby’s poop?

After passing the meconium, breastfed babies will have semi-liquid bowel movements that may contain lumps. Their stool smells like sour milk and is not particularly irritating to their skin. This is another advantage of breastfeeding.

Meanwhile, formula-fed babies’ stools are thicker and have a stronger odour. Baby formula is less digestible than breast milk. It also produces more waste (denser stools) because it contains certain ingredients that a baby’s digestive system can’t absorb.

What are stools like when a baby starts eating complementary foods?

When a child begins to eat solid foods, their stool will become thicker and have more of an odour. The consistency will vary according to their diet. Introducing a new food, for example, can make it softer for a few days.

There’s also no need to worry if you see undigested food (e.g., vegetables or fruit) in your child’s poop. This is a sign that some foods have not had time to be fully absorbed by their digestive system. As they start eating solids, you can help your baby’s digestion by giving them mashed or finely chopped food.

Frequency of bowel movements

During the first few weeks

A newborn generally produces 1 to 3 large stools per day. However, it’s also normal for this number to be higher. In fact, some babies may have as many as 10 bowel movements per day in their first 4 to 6 weeks of life. Breastfed babies tend to have a bowel movement after each feeding.

At this age, babies should have at least one bowel movement every 2 days. If your little one hasn’t pooped in over 48 hours, see a doctor.

As of the 6th week

After 6 weeks, bowel movements may become less frequent and stabilize around 2 to 5 large stools per day. Some babies may even have only one bowel movement a week if they are breastfed, or one every 2 or 3 days if they’re formula-fed.

There’s no need to be concerned if your baby’s bowel movements are infrequent, as long as the stools remain soft.

Before the age of 6 months, babies rarely experience constipation. However, it’s normal for your baby to strain and turn red when they relieve themself.

When should you consult a doctor?

You should consult a doctor if your baby’s poop is:

• White, grey, or pale beige. If this happens, seek medical advice as soon as possible, as it may be a sign of a liver problem.
• Red or black (bloody).
• Hard and dry.
• Very watery and frequent (diarrhea) for more than 24 hours, as your baby could be suffering from gastroenteritis and dehydration.
• Full of mucus for more than a week or two.

Things to keep in mind

• A newborn’s first bowel movements are dark (green or black) and very sticky.
• A breastfed baby’s poop is usually yellow, semi-liquid, and not very smelly.
• Starting from 6 weeks, babies usually have 2 to 5 bowel movements per day, but sometimes only 1 per week if they are breastfed.

Scientific review: Dr. Anne-Claude Bernard-Bonnin, pediatrician Research and writing: The Naître et grandir team Updated: June 2024

Photo: GettyImages/Dziurek