Monthly Vital Statistics Reports

Infant Mortality Statistics from the Linked Birth/Infant Death Data Set – 1996 Period Data

The National Center for Health Statistics (NCHS) has just released a new report that presents infant mortality statistics from the linked birth/infant death data set (1996 linked file). Data are available by a variety of characteristics including race and Hispanic origin of mother, birthweight, period of gestation, sex of infant, plurality, trimester of pregnancy prenatal care began, maternal age, maternal educational attainment, live birth order, marital status, mother’s place of birth, maternal smoking during pregnancy, age at death, and underlying cause of death. Infant mortality rates by these variables are compared and contrasted. Descriptive tabulations of data from the linked file are presented. The data include infant deaths in 1996 which are linked to their corresponding birth certificates, whether the birth occurred in 1996 or 1995. The denominator used to compute infant mortality rates is the NCHS Natality file which included all births in 1995. Data are weighted to compensate for 2.2% of infant death records which could not be linked to their corresponding birth certificates.

Data Highlights:

• In general, mortality rates were lowest for infants born to Asian and Pacific Islander mothers, followed by white, American Indian, and black mothers. Rates for infants of all Hispanic origin mothers combined were comparable to those for infants of non-Hispanic white mothers.
• Infant mortality rates were higher for those infants whose mothers began prenatal care after the first trimester of pregnancy, were teenagers or 40 years of age or older, did not complete high school, were unmarried, or smoked during pregnancy. Infant mortality rates were also higher for male infants, multiple births, and infants born preterm or at low birthweight.
• The leading causes of infant death varied considerably by race and Hispanic origin. For black infants, disorders related to short gestation and unspecified low birthweight was the leading cause of infant death, with an infant mortality rate 4 times that for white infants. For American Indian infants, rates for Sudden infant death syndrome and for Accidents and adverse effects were both 3.2 times higher than those for white infants. For Hispanic and Asian and Pacific Islander mothers infant mortality rates from Sudden infant death syndrome were lower than those for all white infants.

Keywords: infant mortality, infant health, birthweight, maternal characteristics