What is Meconium?

Meconium is a baby’s first stool (poop). It is thick, sticky, and dark green or black. It forms in the baby’s intestines during pregnancy. Meconium consists of materials the baby swallows in the womb, such as amniotic fluid, mucus, bile, and skin cells. This stool is different from the soft, yellow bowel movements babies have after birth.

Typically, a baby passes its first stool after birth, usually within the first 24 to 48 hours. It does not smell because it contains no bacteria, unlike later bowel movements. New parents should expect the baby to have a few meconium-filled diapers before the stools become lighter and softer.

What Happens if Meconium is Passed Before Birth?

In some cases, the baby passes meconium before birth. This can happen if the baby is stressed during labor or if the pregnancy is overdue. When the baby passes it in the womb, it mixes with the amniotic fluid. This condition is called meconium-stained amniotic fluid. Doctors monitor it closely because the baby could inhale the fluid into its lungs.

When a baby inhales or swallows this fluid, it may develop meconium aspiration syndrome (MAS). This condition can cause breathing problems because it can block the baby’s airways. If doctors suspect that it has been passed before birth, they may take extra steps to prevent MAS. After delivery, doctors may suction the baby’s mouth and nose to clear it.

In most cases, meconium aspiration is mild and treatable. However, severe cases may require breathing support or extra oxygen for the baby. Doctors monitor newborns with MAS to ensure they recover fully and do not have lasting effects.

What Should Parents Expect?

Parents should expect their newborn to pass meconium during the first couple of days after birth. The first few dirty diapers will be dark, sticky, and tar-like. As the baby starts feeding, the stool will change in color and consistency, becoming softer and lighter.

The baby’s first stool typically passes after birth. If passed before birth, it may lead to complications like meconium aspiration syndrome. However, with proper care and monitoring, most babies recover without lasting issues.