What colour should my newborn's poo be?
Short answerIn the first week your newborn's poo should change colour in a clear order: black on days 1 and 2 (meconium), then green, then greeny brown, then mustard yellow by around day 5. That sequence is one of the clearest signs that feeding is getting established.
Days 1 and 2: black
Your baby's first poos are meconium: black, thick and sticky, almost tar-like. Passing it is a good sign.
Days 3 and 4: green, then greeny brown
Once milk starts going in, poo gets looser and less sticky, and the colour moves from black to green. This is called a transitional stool. From green it moves towards a greeny brown.
Around day 5: mustard yellow
By around day 5, a breastfed baby's poo is usually soft, loose and yellow, often with little bits in it that look like seeds. Parents often find the seeds alarming. They are one of the most reassuring things a midwife can see.
What if the colour isn't changing?
Black, then green, then brown, then yellow is the sequence midwives use to tell whether feeding is becoming established. If you aren't seeing those changes as expected, speak to your midwife.