Colour changes in a baby's stool are quite common and considered normal. Dark green stool is often found in newborns and even in babies and toddlers from time to time, although the cause is not completely known.
Newborn babies produce meconium, a thick, tar-like stool that is dark green or black. This stool consists of bile, amniotic fluid and skin cells that have collected in his intestines while in the womb.
Green Is Normal
A variety of colours are normal in babies, including green. Typically, dark green stools will quickly return to normal colours within a couple of days and is nothing to worry about. If a stool contains any red, consult a paediatrician.
In strictly breastfed babies, dark green stool could be a response to something the mother ate, such as a sensitivity, allergy or negative reaction.
Formula-fed babies produce stool similar to breastfed babies, except it is thicker in consistency. The colour changes in formula-fed babies stools are normal as well, unless the colour changes to red.
Babies Eating Solids
A dark green stool is often the result of eating something green such as peas, broccoli or spinach.