Meconium aspiration syndrome

Meconium aspiration syndrome (MAS) is a serious breathing condition that affects newborn babies. It happens when a baby breathes in (aspirates) meconium — the baby's first dark, sticky bowel movement — before, during, or just after birth. Normally, meconium passes after birth, but sometimes a baby passes it while still in the womb, often when under stress. If the baby then breathes it in, the meconium can block the airways, irritate the lungs, and make it very hard to breathe. MAS can range from mild to life-threatening. The meconium can plug small airways, cause inflammation, and interfere with a substance called surfactant that keeps the lungs open. This can lead to low oxygen levels, lung collapse, and in severe cases, a dangerous condition called persistent pulmonary hypertension of the newborn (PPHN), where blood pressure in the lungs stays dangerously high. Treatment depends on how severe the condition is. Mild cases may only need extra oxygen and close monitoring. More severe cases may require breathing support with a ventilator, a special therapy called surfactant replacement, inhaled nitric oxide to open blood vessels in the lungs, or in the most critical cases, a heart-lung bypass machine called ECMO (extracorporeal membrane oxygenation). With prompt treatment, most babies recover well, though some may have longer-term lung or developmental effects.

Bring these to your next appointment

• Q1.How severe was my baby's MAS, and what does that mean for their recovery?,What signs should I watch for at home that would mean I need to call for help right away?,Will my baby need any follow-up tests for their lungs or brain development?,Is my baby at higher risk for asthma or breathing problems as they grow?,Should my baby be referred to a developmental specialist for monitoring?,Are there any activity restrictions or special feeding instructions after we go home?,What caused this to happen, and could it affect future pregnancies?

Common questions about Meconium aspiration syndrome