Differential effect of ecologic risk factors on the low birthweight components of African-American, Mexican-American, and non-Latino white infants in Chicago.

This study explored the relationship between ecologic risk factors and infant birthweight. A stratified analysis was performed on all African-American, Mexican-American, and white infants born in Chicago in 1990. One half of African-American mothers (n = 26,799) resided in communities with multiple ecologic risk factors, yet their very low birthweight rates were unaffected by the number of these factors. By contrast, only 5% of Mexican-American mothers (n = 9913) and 5% of white mothers (n = 13,596) lived in communities with multiple ecologic risk factors. Their very low birthweights were twice that of infants born to mothers who resided in communities with no ecologic risk factors. These results indicate that ecologic risk factors affect the very low birthweight rates of Mexican Americans and whites but not African Americans.