Perinatal Indicator: Preterm Birth

Definition

A baby is considered full-term at 40 weeks. Babies born before they have reached 37 weeks in the womb are considered preterm. A baby born before 32 weeks in the womb is considered very preterm.

Why Does This Matter?

 Preterm birth is one of the primary reasons that babies die or become ill in the first year of life. Babies born too early are at high risk for suffering lifelong complications, including developmental, neurological and learning disabilities. They also face a range of chronic health problems and tend to suffer from academic, social, and even economic disadvantages. The cost of caring for a single premature infant can be 25 times higher than the average cost for an infant born on time and at a healthy weight.

For further information, please read the LA Best Babies Network Perinatal Scorecard

  • The rate of preterm birth in LA County is lower than in the U.S. as a whole, but higher than the overall average for the state of California.
  • Rates of preterm births in LA County and California have increased more rapidly than the U.S. since 2002, with the largest increase between 2004 and 2005.
  • Between 2004 and 2005: the US experienced a 1.6% increase in preterm births, California experienced a 5.8% increase in preterm births, and LA County experienced a 7.5% increase in preterm births.
  • Since 2005, rates for preterm births in all geographic regions have remained fairly stable.
  • The U.S. preterm rate peaked at 12.7% in 2005, followed by an increase to 12.8% in 2006, and a decrease back to 12.7% in 2007.
  • The LA County preterm rate peaked at 11.5% in 2005, followed by a decrease to 11.3% in 2006, and an increase to 11.4% in 2007.
  • The California preterm rate peaked at 10.9% in 2005, followed by a decrease to 10.8% in 2006, and an increase back to 10.9% in 2007.
  • Nationally, the preterm birth rate declined 4% between 2006 and 2008, from 12.8% to 12.3% of live births.
  • In Los Angeles County, the rate of preterm birth before 32 weeks gestation, is 2.5 times higher among African Americans than whites, 2.3 times higher among American Indians, and 1.2 times higher among Latinos.
  • American Indian/Native Alaskan and African Americans have the highest rates of preterm births at the earliest gestational age

preterm

Sources: County of  Los Angeles Department of Public Health, Maternal, Child & Adolescent Health Programs; March of Dimes Perinatal Data Center, 2009.

Percent of Preterm Births by Race/Ethnicity, Los Angeles County (2007)

Gestational Age
Ethnicity/Race
White
Black
American Indian/ Native American
Asian
Hawaiian/ Pacific
Islander
Hispanic
LAC
< 20 wks
0.0%
0.1%
0.0%
0.0%
0.2%
0.1%
0.1%
≥ 20 wks and < 24 wks
0.1%
0.5%
0.0%
0.1%
0.2%
0.1%
0.2%
≥ 24 wks and < 28 wks
0.3%
0.9%
1.7%
0.2%
0.2%
0.4%
0.4%
≥ 28 wks and < 32wks
0.9%
2%
1.3%
0.8%
1.2%
1.0%
1.0%
≥ 32 wks and < 34 wks
1.5%
2.3%
3.8%
1.2%
1.5%
1.4%
1.5%
≥ 34 wks and < 37wks
7.8%
10.1%
8.9%
7.5%
6.9%
8.4%
8.3%

 

preterm by race

Preterm weeks

Source: California Department of Public Health, Center for Health Statistics, OHIR Vital Statistics Section, 2007 Vital Statistics, prepared by LA Best Babies Network, 2009.
Photo courtesy Cheryl