What is meconium?

Meconium is defined as the first stool passed by a newborn baby. This substance is typically greenish-black in color and is composed of materials ingested by the fetus during pregnancy, including amniotic fluid, bile, and cells shed from the intestinal lining. Meconium is usually thick and sticky and can be an important indicator of the health of a newborn as its presence and characteristics can provide insights into the baby's well-being and the conditions in utero.

While the other options mention various aspects of infant care and nutrition, they do not accurately describe meconium. Maternal milk refers to breast milk produced by the mother, which nourishes the newborn after birth, while the first food introduced to infants generally refers to solid foods introduced during weaning. A nutrient supplement for babies relates to products designed to provide additional vitamins and minerals, which is distinct from the natural first stool of a newborn.