Abnormal stooling

When should I see my health-care provider about my baby’s poop?

Major changes in the colour and consistency of your baby’s stools (poop), as well as in your baby’s pattern of passing stools, can indicate a problem and need attention from your health-care providers. These include (a) excessive and painful straining or pushing by your baby to pass a stool, (b) constipation, if your baby’s stools are hard and dry, or (c) blood in the stool or vomit. See your health-care provider urgently if your baby has (a) white or grey stools, (b) blood in the stool, (c) is vomiting blood, or (d) showing other signs of an emergency.

A) Major changes in stooling

Some changes, such as the gradual slowing of how often a breastfed baby stools or a change from yellow to green stools in a baby whose mother has a lot of milk are normal.

A change in the colour or consistency of a baby’s stool (poop) can also indicate a problem. This is especially likely if the changes happen suddenly or are accompanied by other signs of illness. All of the following situations require attention from your health-care providers.

B) Constipation

1) Excess straining or pushing

Normal babies have frequent, painful cramps during and after feeding for the first few months of life. This is the gastrocolic reflex. Some babies also strain or push for a few minutes to have a bowel movement. This too is normal, but if the straining or pushing is extremely painful, long-lasting, or frequent, please consult your health-care providers.

2) Constipation

A diagnosis of constipation is based on the nature of the baby’s stools. A baby is constipated if the stools are hard and dry. Constipated babies often strain or have pain while trying to pass these stools. They may also pass a stool less often.

a) Infant formula use

Constipation is uncommon in breastfed babies and more common in babies fed infant formula (Pattison 2019; Quinlan 1995).

There is some evidence that this is because of the differences in the types of fat in breast milk and infant formula (Borschel 2014; Lasekan 2017). Breast milk has unique animal-based fats instead of the plant-based fats found in infant formula. Breast milk fats are easier to digest and produce larger, softer stools than those of infant formula-fed babies (Miles 2017; Petit 2017; Yao 2014). Any breast milk tends to improve stool consistency and prevent constipation (Çamurdan 2014).

Constipation in infant formula-fed babies may be helped by changing the type of infant formula. 

b) Illness in the baby

Constipation can be caused by a large and varied number of illnesses. Causes include:

  • Celiac disease
  • Cystic fibrosis
  • Hormone problems (low thyroid hormone levels, diabetes)
  • Genetic disorders (connective tissue diseases)
  • Abnormalities of the structure of the bowel
  • Spinal cord abnormalities
  • Allergic reactions (Caubet 2017; Tabbers 2014).
  • Medication
  • Lead poisoning

C) Diarrhea

The traditional definition of diarrhea is three or more loose, watery stools in 24 hours. Healthy breastfeeding babies often have more frequent stools, making the diagnosis a little more difficult.

Babies are more likely to have illness-related diarrhea if (Levine 2017):

  • There is more water than solid material in the stool.
  • There is blood or large amounts of mucous in the stool.
  • There is a sudden change in the baby’s stool or stooling patterns.
  • They show other signs of illness.

D) Blood in the stool

Blood present in the baby's stool.

Blood in the baby’s digestive tract can turn the baby’s spit-upvomit, or stool red. If not eliminated quickly, such blood will be digested in the next few hours, turning it black in colour. Such babies may have black flecks or spots in the baby’s spit-up or vomit or very dark or black stools.

1) Sick babies

Blood in the stool can be a sign of major illness in the baby and needs to be taken seriously. Blood in the stool may be caused by any of the following:

  • A tear in the swallowing tube (esophagus) after vomiting
  • A tear in the skin of the anus (an anal fissure)
  • A bowel abnormality that often requires surgery, including:
    • A duplication of the bowel
    • A twisting of the bowel (volvulus)
    • The bowel telescoping into itself (intussusception)
    • A bowel that does not have enough nerves to allow it to function properly (Hirschsprung’s disease)
    • An extra piece of bowel (Meckel’s diverticulum)
  • An abnormality of the blood vessels of the bowel
  • An allergy to cow’s milk protein or other foods that the breastfeeding mother or her baby is eating
  • Other causes of inflammation or infection of the stomach or bowels
  • A severe bowel condition seen mostly in premature babies (necrotizing enterocolitis)
  • The baby’s blood not clotting properly as when the baby does not have enough vitamin K

2) Other causes of blood in the stool

Blood in the stool can also come from:

An Apt test on the blood can determine whether it is coming from the mother or her newborn baby.

A bleeding diaper rash can result in blood in the diaper.

Iron supplements given to the baby can mimic blood in the stool as both can turn the stool dark.

E) Emergencies

See your health-care provider urgently or go the nearest emergency department if the baby:

  • Is passing stools that contain more than just specks or streaks of blood.
  • Has stools that look like red currant jelly or are a thick, black paste.
  • Is vomiting blood.

Babies may also show other signs that they are sick including:

White or grey stools can be caused by blocked ducts (tubes) in the liver (biliary atresia). This prevents bile from leaving the liver. Babies with this condition will also have yellow skin. They require urgent surgery.


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