What should my newborn's poo look like?
A newborn’s first poo is usually dark and sticky. It changes over the first days, and patterns vary between babies.
The short answer
The NHS describes a newborn’s first poo, called meconium, as sticky and greenish black. After a few days, it usually becomes yellow or mustard coloured. Your baby’s feeding method affects its texture and appearance.
Expect a change in the first days
The NHS describes meconium, a newborn’s first poo, as sticky and greenish black. Babies may pass it during or after birth, or within the first 48 hours. After a few days, poo often changes to a yellow or mustard colour.
The exact timing and appearance can vary. Breastfed babies often have looser poo, while formula fed babies may have firmer and darker poo. Some formulas can make poo look dark green. A change in feeding can also change its texture.
Look at the whole pattern
There is no single colour or schedule that explains how a baby is doing. The NHS says babies may strain or cry while pooing and can still have soft poo after several days without a bowel movement. Age, feeding, wet nappies and the baby’s overall condition all matter.
Contact your health visitor, doctor or midwife if poo becomes very watery, unusually hard, has blood in it or looks pale. A pale colour can be a sign of jaundice and should be discussed with a health professional. Follow local advice for urgent concerns.
Use a record to describe changes
If you’re asked to keep notes, write down what you saw and when. A simple record can make it easier to describe a pattern at an appointment, but it can’t diagnose constipation, jaundice or a feeding problem.
BabyDays can record wet and dirty nappies. It doesn’t check their appearance. Ask your care team which details matter for your baby, especially if your baby was born early or has a feeding plan.
Sources and further reading
Sources checked 12 October 2026. This page doesn’t replace advice from your own doctor.