Meconium and Transitional Stool: A Newborn Poop Timeline
Key takeaway
Black or dark green, sticky meconium is expected during the first days of life. As feeding becomes established, newborn stools typically transition toward yellow-green and then a pattern influenced by feeding type.
The first diapers after birth often look nothing like later diapers. In the first days of life, babies pass meconium: a thick, sticky material that is usually black or very dark green. This is expected during the newborn transition.
First days: meconium
Meconium develops before birth and is commonly passed in the first few days. It can look tar-like and may be difficult to wipe. In this early period, black or dark green stool is usually expected.
The transition as feeding is established
As meconium passes, stool often becomes lighter and may look greenish before shifting again. For breastfed babies, stools are commonly yellow and loose with seed-like particles. Formula-fed babies often have tan or yellow stools that are somewhat firmer, and green can still be normal.
What matters in the first week
Newborn stool is only one part of the picture. Your maternity team or pediatric clinician can help with questions about feeding, wet diapers, weight checks, jaundice, or a pattern that is not changing as expected.
Get medical advice promptly if
Important: Timelines vary. This information is a guide for discussion with your newborn’s clinical team, not a diagnosis.
Sources and further reading
Educational summary based on the pediatric and public-health resources below. Sources do not replace individual medical advice.
BabyPoop AI provides educational information only and does not replace professional medical advice, diagnosis, or treatment. If your baby seems unwell or you are concerned, contact a qualified clinician.
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