Sometimes — before birth or during labor and delivery — a baby inhales a mixture of amniotic fluid and a substance called meconium into his lungs. This is called meconium aspiration syndrome (MAS), ...

Meconium aspiration syndrome (MAS) remains a serious neonatal respiratory disorder that occurs when newborns inhale meconium‐stained amniotic fluid during delivery. This condition, often associated ...

Meconium is a completely normal part of your baby’s first days. It is their very first stool, which is usually passed after birth. But, in some cases, babies release meconium while still in the womb.

Meconium is a thick substance that lines a baby’s intestines in the womb. A baby usually passes meconium after birth, but if they pass it early, the amniotic fluid may become meconium-stained.