First Time User? Sign Up Now
First Time User? Enroll now.
Home > Health Library > Meconium
Meconium is a thick, greenish black substance that forms in the intestines of an unborn child (fetus). As the fetus swallows and digests the fluid (amniotic fluid) inside the womb, it produces meconium.
Meconium in the amniotic fluid may be a sign that the newborn experienced stress before birth. If meconium gets into the baby's lungs, it can cause irritation and inflammation of the lungs.
When the baby is born, meconium is the first stool the baby passes. Most newborns pass the meconium within 48 hours after birth.
If your baby doesn't pass his or her first stool within the usual time frame, it may be a sign of a blocked intestine or another problem. Your baby may need treatment to remove the stool from the body.
Current as of: February 10, 2021
Author: Healthwise Staff
Medical Review:Adam Husney MD - Family Medicine & John Pope MD - Pediatrics & Kathleen Romito MD - Family Medicine
To learn more about Healthwise, visit Healthwise.org.
© 1995-2021 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.