The first stool a newborn passes, made up of amniotic fluid, bile, and mucus. Meconium resembles tar in consistency and color. Its passing is a key indictor of the infant’s health and gastrointestinal patency (clear passage).
Infants with healthy gastrointestinal systems pass their first meconium stools within 24 hours of birth and may continue to pass it for two or three days.
An infant that fails to pass it within 24 hours may have a congenital malformation of the gastrointestinal tract such as bowel atresia.
A complication common in infants who have cystic fibrosis, a genetic disorder that affects multiple body systems, is meconium ileus in which impacted meconium obstructs the bowel. Enemas often relieve the impaction; when they do not, surgery is necessary.
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