The large disparities in the proportion of preterm births and other birth outcomes between racial and ethnic groups in the United States have been persistent and troubling. The categorization of racial and ethnic groups is difficult and controversial because there is no simple method for defining these groups or subgroups. However, it is important to collect data on race and ethnicity to document and assess health status and health outcomes for various groups of the U.S. population. The U.S. Office of Management and Budget provides a classification system of race and ethnicity to study the social, demographic, health, and economic characteristics of various groups in the United States (EOP, 1995). That system comprises five racial group categories (American Indian or Alaska Native, Asian, black or African American, Native Hawaiian or other Pacific Islander, and white) and two categories for ethnic groups (Hispanic or Latino and not Hispanic or Latino) (EOP, 1995). Newborn infants and fetal deaths are categorized on the basis of the self-reported race of the mother (CDC, 2005d). The data presented in this section were obtained from the National Center for Health Statistics, and the discussion in this section uses this classification system.

Explaining and trying to remedy the significant racial disparities in the proportion of preterm births should be a priority for the research and the health care communities. The most striking disparities are between non-Hispanic white and black women and between Asian or Pacific Islander women and black women (Figure 1-8). Although the highest percentages of

FIGURE 1-8 Preterm births as a percent of live births, by race and ethnicity, 1992 to 2003.

SOURCE: CDC (2004a).