Infant mortality is a measure of the number of infants who die before reaching their first birthday. Infant mortality rates tell how many babies die each year for every thousand babies that are born. Because the rates reflect the well-being of the most dependent members of a society, they are often interpreted as a measure of how well the society is able to take care of its people. For this reason, comparing infant mortality rates of different nations or communities is a way of evaluating a society’s standard of living.
Deaths during the first year after birth are divided into two categories, depending on when they occur. Neonatal deaths occur during the first 27 days after birth. Postneonatal deaths occur from 28 days of age to age 1. Factors that contribute to a baby’s death are different in each of these two periods. Neonatal deaths are usually related to conditions that the infant is born with. For example, many neonatal deaths occur because the infant was born too early or too small to ensure survival. Postneonatal deaths are more often related to the infant’s living environment after birth. Common factors in such deaths include whether the baby receives immunizations against communicable diseases and whether the infant is provided adequate food, shelter, and health care.
Infant mortality rates vary greatly worldwide. The highest rates occur in developing nations in Africa, Asia, and Central and South America. The lowest infant mortality rates are found in industrialized countries that offer comprehensive health care, such as Finland, Japan, and Sweden. Infant mortality rates in the United States are high compared to other developed nations, in part because of the high rates of infant death among impoverished minority groups.
