Meconium (antenatal period)

Meconium is the earliest stools of an infant. Unlike later feces, meconium is composed of materials ingested during the time the infant spends in the uterus. Meconium is almost sterile, unlike later feces, is viscous and sticky like tar, and has no odor. It should be completely passed by the end of the first few days of life, with the stools progressing toward yellow.  Meconium is normally stored in the infant’s bowel until after birth, but sometimes it is expelled into the amniotic fluid prior to birth or during labor and delivery. Meconium liquor is recognized by medical staff as a sign of fetal distress, and puts the neonate at risk of meconium aspiration.