“No statistic expresses more eloquently the difference between a society of sufficiency and a society of deprivation than the infant mortality rate.” In the U.S. presently, low birthweight infants represents a large proportion of infant mortality deaths. While the infant mortality rate has decreased dramatically since the beginning of the twentieth century, the incidence rate for low birthweight has remained stable. The incidence of low birth weight is expected to be higher among all minority groups since they represent a disproportionate proportion of low-income strata. However, the Mexican-American population, which shares several sociodemographic risk factors with the black population, has an infant mortality rate that is very similar to the white population. A study to evaluate some of the behavioral, demographic, and medical characteristics among racial minority groups of similar socioeconomic status was conducted among Mexican-American and black women who gave birth to live infants at Cook County Hospital in Chicago during 1986. The study enrolled 236 blacks and 236 Mexican-American women.

The incidence of low birthweight infants was 16.1% (38/236) for the blacks and 5.9% (14/236) for the Mexican-Americans. While the incidence of preterm delivery was 20% lower among Mexican-Americans than blacks, the difference was not significant. Regarding the sociodemographic characteristics, Mexican-American women tended to be older, married, less educated, and less likely to be on welfare and recipients of food stamps than the black women. Furthermore, the Mexican-American fathers were more likely to be employed and the black women were more likely to be employed outside the house (16% vs. 6%). Significant differences were also observed for the behavioral variables. Black women tended to smoke and use nonmedical drugs during their pregnancy than Mexican-American women. Also, a higher percentage (12% vs. 6%) of the black women gained less than 15 lb during pregnancy. Regarding the psychosocial variables, Mexican-American women more often reported that their pregnancy was planned and that they were breast feeding, while the black women more often reported increased family support. Within the subgroups comprised of only women with behavioral or medical risk factors, no significant difference between incidence of low birthweight among the Mexican-American and black women was observed. In contrast, among the women without any complications, incidence of low birth weight among the Mexican-American women (3/138 or 2.2%) was significantly lower than among the black women (11/98 or 11.2%).

Among the subgroups of Mexican-American and black women with behavioral and medical complications, the difference in the incidence of low birthweight was not significant. This may be partly the result of limited sample size. However, when neither behavioral nor medical complications were present, the Mexican-American women had a low incidence of low birth weight of 2.2 % despite their cultural displacement, language barriers and poverty. In contrast, the incidence rate among the black women without behavioral and medical complications was still 12.2%. Furthermore, the Mexican-American women who use Cook County Hospital were generally recent immigrants from impoverished small towns in search of employment, and not immigrants who are healthier or financially advantaged. Despite the similar socioeconomic status among the Mexican-American and black women, the groups are quite dissimilar. The black women in the study shared many similar behavioral and demographic characteristics that are prevalent among the urban poor, regardless of race. While the Mexican-American women in the study were similarly impoverished as the black women, the Mexican-American women were not urban acclimated. The sociocultural attributes of the Mexican-Americans may be conducive to delivery of health infants and should be supported and preserved. Nevertheless, the unhealthy lifestyle of the urban poor should be addressed.