Your newborn baby’s stools (poo)

New parents can sometimes feel a little unsure as to what they can expect to find in their newborn baby’s nappy. This brief article provides information on the normal and progressive changes in your baby’s stools (poo). These changes are a clear and visible indication that your baby’s gastrointestinal tract (ie their stomach and bowels) are functioning as they should be.

The very first stool that your baby passes is called ‘meconium’. Meconium is a substance that is inside your baby’s bowel while they are inside the womb. It is a very dark greenish, almost black-coloured, sticky, tar-like substance which is actually sterile! Meconium is made up of amniotic fluid (ie the waters surrounding your baby), mucus, ‘normal’ secretions from inside your baby’s intestines and also desquamated cells. NB. ‘Desquamated cells’ are cells that have been lost from the upper layers of your baby’s tissues or the structures inside their body. ‘Desquamation’ is an entirely normal process whereby cells in the upper layer are shed to allow new cells underneath to develop.

IMG_1394Around the third day post birth, you will notice that your baby’s meconium stools start to be replaced by what is commonly referred to as ‘changing stools’. These stools are a slightly yellowish-colour which reflect your baby’s digestion of the breast or formula milk that they are receiving.

IMG_1391Changing stools last for around three to four days before changing to what your midwife will describe as a ‘milk’ stool. Your baby’s milk stools will have a slightly different appearance and odour depending on your chosen method of infant feeding.

a). Breastfed babies have soft, yellow-coloured stools that have a rather sour odour

b). Babies receiving formula milk tend to have yellow stools that are a little paler with a firmer consistency and which tend to be a little more ‘smelly’.

IMG_1388The ph of your baby’s stools will be anything between the ranges of 5.5 to 7.5 (NB. The ph value indicates the acidity or alkalinity of a substance with 7 being neutral. Values that are lower indicate more acidity and higher values are more alkaline).

Babies who are breastfed have stools with a lower ph – this acidity helps to protect them from infection and gastroenteritis (ie inflammation of the stomach or bowel caused by viral or bacterial infection which often causes diarrhoea and vomiting). The acidity of your baby’s stools and their contact with your newborn’s skin is why it is recommended that you change your baby’s nappy as soon as they have filled it. For further information see our article on ‘Nappy rash (Nappy dermatitis)’.

Where you have any concerns about your baby’s stools, you should always contact your midwife, health visitor or GP for their advice. You should also try and retain the nappy to show your health care professional its contents, as this can help them to distinguish between normal baby stools and those which might indicate a potential concern.

Baldassarre ME, Laneve A, Fanelli M et al (2010). Duration of meconium passage in preterm and term infants. Archives of Disease in Childhood: Fetal and Neonatal Edition 95(1):F74-F75.

Bekkali N, Hamers SL, Schipperus MR et al (2008). Duration of meconium passage in preterm and term infants. Archives of Disease in Childhood: Fetal and Neonatal Edition 93(5):F376-F379.

Griffin A, Beattie RM (2001). Normal bowel habit during the first six weeks in healthy term infants. Ambulatory Child Health 7(1):23-26.

Shrago LC, Reifsnider E, Insel K (2006). The neonatal bowel output study: indicators of adequate breast milk intake in neonates. Pediatric Nursing 32(3):195-201.

Steer CD, Emond AM, Golding J et al (2009). The variation in stool patterns from 1 to 42 months: a population-based observational study. Archives of Disease in Childhood  94(3):231-233.