• Fetal and Infant Mortality (FIMR)

• Infant Health (IHR)

• Pregnancy Outcomes (POR)

• Maternal Risks (MRR)

• Teen Risks (TRR)

• Maternal Interventions (MIR)

Fetal and Infant Mortality

Subpopulation Definitions

• Infant mortality (IMR) rate—number of infant deaths per 1,000 live births.

• Neonatal mortality (NMR) rate—number of deaths of infants less than 28 days old per 1,000 live births.

• Postneonatal mortality (PNR) rate—number of deaths of infants age 28 days to 1 year per 1,000 live births.

• Perinatal mortality (PMR) rate—the sum of late fetal deaths plus infant deaths within 7 days of birth divided by the sum of live births plus late fetal deaths, and stated per 1,000 live births plus late fetal deaths.

Population—all infants born live and late fetal deaths to residents of the United States and US territories for the selected time period, geographic area and demographic composition.

Data Source—National Center for Health Statistics.

Note 1:Neonatal deaths are not excluded from the denominator of the postneonatal mortality rate.

Note 2: Late fetal deaths are defined as gestations of 28 weeks or longer.

Infant Health

Subpopulation Definitions:

• Low birth weight (LBW) rate—number of live born infants with a birth weight of less than 2,500 grams per 100 live births.
• Very low birth weight (VLB) rate—number of live born infants with a birth weight of less than 1,500 grams per 100 live births.
• Preterm delivery (PTD) rate—number of live born infants with a gestational age at delivery of less than 37 weeks per 100 live births.

Population—all infants born live to residents of the United States and US territories for the selected time period, geographic area and demographic composition. 

Data Source—National Center for Health Statistics.

Pregnancy Outcomes

Subpopulation Definitions:

• Fertility (LB) rate—number of women who had a live born infant per 1,000 women.
• Fetal loss (FD) rate—number of women who had a dead born infant per 100,000 women.

Population—all women aged 10 through 49 years (reproductive age) who are residents of the United States and US territories for the selected time period, geographic area and demographic composition.

Data Sources—National Center for Health Statistics and the US Census.

Note 1: Age group rates for pregnancy outcomes are calculated with the same age women in both the numerator and denominator with the following exceptions: (1) the 10–54 age group is calculated with a numerator of 10–54 and a denominator of 15–44 to more closely match historical data, and (2) the 40–54 age group is calculated with a numerator of 40–54 and a denominator of 40–49 because most births to women over age 44 are to women age 45–49.

Note 2: Fetal loss is defined as gestations of 22 weeks or longer.

Maternal Risks

Subpopulation Definitions:

• Smoking ( SMK) Percent—number of women who had a live birth and smoked tobacco at any time during her pregnancy per 100 women who had a live birth.
• Unmarried (UM) Percent —number of unmarried women who had live birth per 100 women who had a live birth.
• Educational attainment (EDA) Percent—number of women who had a live birth and had attained less than a high school education at the time of delivery per 100 women who had a live birth.
• Multiple gestation (MG) Percent—number of women who had a live birth and gestation with two or more fetuses per 100 women who had a live birth.

Population—all women aged 10 through 54 years (reproductive age) who are residents of the United States and US territories for the selected time period, geographic area and demographic composition.

Data Sources—National Center for Health Statistics and the US Census.

Note: Educational attainment for women age 20 years and younger is defined as more than two years older than modal age for grade.

Teen Risks

Subpopulation Definitions:

• Educational attainment (EDA) Percent—number of teen women who had a live birth and who were more than two years older than expected for grade level per 100 teen women who had a live birth.
• Late/no care—Prenatal care began in the 3rd trimester or no prenatal care (NPC) Percent: number of teen women who had a live birth and received no prenatal care or prenatal care was begun in the third trimester per 100 teen women who had a live birth.

Population—all women aged 10 through 19 years (teens) who are residents of the United States and US territories for the selected time period, geographic area and demographic composition.

Data Sources—National Center for Health Statistics and the U.S. Census.

Maternal Interventions

Subpopulation Definitions:

• 1st Trimester care—Prenatal care began in the 1st trimester of pregnancy (P1T) Percent: number of women who had a live born infant who began their prenatal care in the 1st trimester of pregnancy per 100 women who had a live birth.

Population—all women aged 10 through 54 years (reproductive age) who are residents of the United States and US territories for the selected time period, geographic area and demographic composition.

Data Sources—National Center for Health Statistics and the US Census.

Page last reviewed: 7/28/08
Page last modified: 1/29/07
Content source: Division of Reproductive Health, National Center for Chronic Disease Prevention and Health Promotion