that the weight of the evidence in this field has used low birth weight to assess this population.

The second theme that guided the committee’s approach to its task was the troubling evidence of long-standing disparities in the rates of preterm birth among different groups in the U.S. population. Certain subpopulations categorized by their racial, ethnic, or socioeconomic status have a greater risk and a higher proportion of preterm births. The most striking rates are for African-American women. In 2003, the proportions of preterm births for specific racial and ethnic groups were 10.5 percent for Asian Pacific Islander women, 11.5 percent for non-Hispanic white women, 11.9 percent for Hispanic women, 13.5 percent for American Indian/Alaska Native women, and 17.8 percent for non-Hispanic African American women (CDC, 2005i). Although the rate for African American women has decreased in the last decade, overall these women continue to experience a much higher proportion of preterm births. The most notable increase in the percentages of preterm birth from 2001 to 2003 was for white non-Hispanic, American Indian, and Hispanic groups. Although the rates for Hispanic and Asian Pacific Islander women are the lowest among the ethnic and racial minority groups in the United States, these are not homogeneous populations, and considerable variation in the rates of preterm birth exist among subpopulations.

The third theme that guided the committee’s framing of this problem and formulation of recommendations is the complexity of the problem that it was charged with assessing. Preterm birth is not one disease for which there is likely to be one solution or cure. Rather, the committee considers preterm birth a cluster of problems with a set of overlapping factors of influence that are interrelated. This complexity makes the detection of solutions to the problem difficult. There will be no silver bullet. The complex nature of this problem led the committee to consider its causes in an integrated manner. These causes are multiple and may vary for different populations. Individual-level behavioral and psychosocial factors, neighborhood social characteristics, environmental exposures, medical conditions, infertility treatments, biological factors, and genetics may play roles to various degrees. Many of these factors are present together, particularly among women of low socioeconomic or minority status.

After reviewing the evidence, the committee proposes a research agenda for investigating the problem of preterm birth. The agenda is presented to help focus and direct research efforts. The recommendations are grouped and prioritized and therefore presented in a different sequence than they appear in the full report; however, their numeric designation remains the same.

Priority areas are grouped as follows: