Improvement in infant and perinatal mortality in the United States, 1965--1973: I. Priorities for intervention.

Changes in United States infant and perinatal mortality in the period 1965--1973 were examined by race, age at death or length of gestation, and degree of urbanization. The decline of postneonatal mortality rates was greater than the declines of fetal and neonatal mortality rates. Other-than white infant and fetal mortality rates improved more than the white rates, except in the first day of life. Postneonatal mortality rates improved more in rural than in urban areas, while neonatal and perinatal mortality rates improved more in urban areas than in rural. These improvements in mortality rates have occurred at the same time as changes in medical techniques and the organization and availability of health services, improvements in economic conditions and standards of living, and changes in the demographic characteristics of the child-bearing population of the United States. Each of these changes was in a direction expected to have a favorable effect on infant and perinatal mortality. Nevertheless, the improvement of infant mortality rates has not changed the relative position of the United States in comparison with other countries. Programs to improve infant and perinatal mortality can use the data in this study to define high priority target groups using a method based on the size of the problem in the target group, the severity of the problem, and the amount and direction of change.

Urbanization and differentials in white and nonwhite infant mortality.

This study analyzes infant deaths in the United States, 1962 to 1967, by place of residence, to determine to what degree variations in age at death are related to degree of urbanization and race. Results of the study indicate that: (1) after one day of life infant mortality increases progressively as degree of urbanization decreases; (2) the differences between urban and rural death rates are greatest in the posthebdomadal (1 week or older) period; (3) in all age groups at all levels of urbanization, the nonwhite infant is at a marked disadvantage relative to the white infant; (4) the older the infant, the greater the disadvantage for nonwhite infants in rural areas; (5) had the white infant mortality rate prevailed among the nonwhite population over the six-year period from 1962 to 1967 an estimated annual total of 11,597 nonwhite infants would have survived their first year of life; (6) 40% of the excess deaths are in infants under 7 days and 60% in the posthebdomadal period; (7) fetal death rates increase progressively as degree of urbanization decreases, complementing a direct relationship between under 1 day mortality and urbanization resulting in a level trend for perinatal mortality.