The stool colour of fully breastfed and bottle-fed infants may vary from light yellow to green to brown.² The colour may change repeatedly over the course of their development and if they are given different foods. A green stool is often observed when HA formula is administered to infants, but also when they are on a breast milk diet. This is normal and nothing to worry about. It is caused by the rapid transit time through the intestine due to the broken down protein, which means the green bile pigment is less broken down into yellowish and later brownish pigments. Discoloured stools are a warning sign of an obstruction in the bile duct. Stool colour cards are a tool for parents to assess whether the infant’s stool colour requires evaluation by a paediatrician.³

The normal range of stool frequency is very wide. Breastfed children defecate between 10 times a day and once every one to two weeks. Bottle-fed infants empty their bowels less frequently (1 to 3 times a day).⁴
The stool consistency in breastfed infants is usually liquid to mushy. In bottle-fed infants, it tends to be more mushy.⁴ Formulae containing galacto-oligosaccharides (GOS) can lead to softer stools, similar to those produced by breastfed babies.

Diarrhoea is recognisable by a sudden decrease in consistency and/or an increase in individual stool frequency (≥3 times/24 hours).⁵
If an infant has fewer than three bowel movements per week with hard and perhaps even painful bowel movements, it is called constipation. Fully breastfed infants are an exception, as they can only have a bowel movement once every 14 days.⁶
In the event of diarrhoea or prolonged constipation, parents should seek medical advice.

Infants often have trouble defecating during the first months of life. Baby gymnastics and letting the infant kick can trigger some movement in the intestine and stimulate digestion. Gentle clockwise stroking around the belly button has also been found to help. Check that the dosage instructions have been followed when preparing formula for bottle- fed infants. Meals that are too concentrated can put a strain on the infant’s digestive and excretory organs. Never manipulate the anus (e.g. by inserting a clinical thermometer) to provoke bowel movements.
Defecation dificulties are often the result of an initial functional disorder of bowel coordination. Some children also cry before passing a loose stool. This is harmless and is called dyschezia.⁷ If problems with bowel movements persist, consult a paediatrician. After consultation, it may be possible to switch to a Comfort Special Formula, which helps regulate digestion and loosen stools.

A change in diet, e.g. switching to a different formula or from breast milk to formula, may cause changes in stool colour, consistency and frequency or even lead to temporary flatulence. This is because the intestinal microbiota first has to get used to the new formula. It is helpful to make the switch bottle by bottle by giving one bottle more of the new formula each day.
For the infant’s health, it is important to follow the prescribed dosage instructions and use the measuring scoop supplied with the pack. Mixing powders of different formulae in one bottle can make it harder for an infant to digest the resulting formula.

References:
¹ Bundeszentrale für gesundheitliche Aufklärung. Version: 02/06/2023 www.kindergesundheit-info. de (downloaded on 06/11/2024).
² Bekkali N et al. Infant Stool Form Scale: Development and Results. J Pediatr. 2009; 154(4): 521-526.
³ Borgeat M et al. BMJ Paediatr Open. 2018; 29;2(1).
⁴ Posovszky C. GPGE-Leitlinie: Akute infektiöse Gastroenteritis im Säuglings-, Kindes- und Jugendalter (2024). www.awmf.org.
⁵ Guraino A et al. ESPGHAN/NASPGHAN Guidelines: Management of Acute Gastroenteritis in Children in Europe: Update 2014. JPGN 2014; 59: 132-152.
⁶ Drossman D A & Hasler W L. Rome IV-Functional GI disorders: Disorders of gut-brain interaction. Gastroenterology 2016; 150(6), 1257-1261.
⁷ Guandalini S et al. Textbook of Pediatric Gastroenterology, Hepatology and Nutrition: A Comprehensive Guide. 2021. Springer International Publishing.

Important information: Breastfeeding is best for babies. Infant formula should only be given upon the advice of paediatricians, midwives or other independent experts.