Paradox found (again): infant mortality among the Mexican-origin population in the United States.

Recent research suggests that the favorable mortality outcomes for the Mexican immigrant population in the United States may largely be attributable to selective out-migration among Mexican immigrants, resulting in artificially low recorded death rates for the Mexican-origin population. In this paper we calculate detailed age-specific infant mortality rates by maternal race/ethnicity and nativity for two important reasons: (1) it is extremely unlikely that women of Mexican origin would migrate to Mexico with newborn babies, especially if the infants were only afew hours or afew days old; and (2) more than 50% of all infant deaths in the United States occur during the first week of life, when the chances of out-migration are very small. We use concatenated data from the U.S. linked birth and infant death cohort files from 1995 to 2000, which provides us with over 20 million births and more than 150,000 infant deaths to analyze. Our results clearly show that first-hour, first-day, and first-week mortality rates among infants born in the United States to Mexican immigrant women are about 10% lower than those experienced by infants of non-Hispanic, white U.S.-born women. It is extremely unlikely that such favorable rates are artificially caused by the out-migration of Mexican-origin women and infants, as we demonstrate with a simulation exercise. Further, infants born to U.S.-born Mexican American women exhibit rates of mortality that are statistically equal to those of non-Hispanic white women during the first weeks of life and fare considerably better than infants born to non-Hispanic black women, with whom they share similar socioeconomic profiles. These patterns are all consistent with the definition of the epidemiologic paradox as originally proposed by Markides and Coreil (1986).

The increasing racial disparity in infant mortality: respiratory distress syndrome and other causes.

Although substantial declines in infant mortality rates have occurred across racial/ethnic groups, there has been a marked increase in relative black-white disparity in the risk of infant death over the past two decades. The objective of our analysis was to gain insight into the reasons for this growing inequality on the basis of data from linked cohort files for 1989-1990 and 1995-1998. We found a nationwide reversal from a survival advantage to a survival disadvantage for blacks with respect to respiratory distress syndrome over this period. The results are consistent with the view that the potential for a widening of the relative racial gap in infant mortality is high when innovations in health care occur in a continuing context of social inequality. As expected, the results for other causes of infant mortality, although similar, are less striking. Models of absolute change demonstrate that among low-weight births, absolute declines in mortality were greater for white infants than for black infants.

Low birth weight in Mexico: new evidence from a multi-site postpartum hospital survey.

OBJECTIVE: To identify factors related to cases of low birth weight among a sample of Mexican women. MATERIAL AND METHODS: The present analysis utilizes data from a post partum survey of 565 women implemented in eight different social security hospitals in western Mexico during 2001. Women giving birth to low weight infants (2.5 kgs) were oversampled and make up half of the sample. RESULTS: A series of logistic regression equations are presented that estimate the risk of low birth weight. Study findings indicate that, although behavioral factors appear to be highly significant in predicting the odds of low birth weight, socioeconomic and sociodemographic factors were found to be important in determining utilization of prenatal care. CONCLUSIONS: The key role of behavioral characteristics in determining low birth weight risk and the role of socioeconomic and sociodemographic factors in determining prenatal care usage highlights the need to improve prenatal care utilization by disadvantaged populations.

Low birth weight in Mexico: new evidence from a multi-site postpartum hospital survey

OBJETIVO: Objetivo. Identificar los factores relacionados con el bajo peso al nacer en mujeres mexicanas. MATERIAL Y MÉTODOS: Se analizan datos de una encuesta recientemente aplicada en 2001 a 565 mujeres en condición de posparto, en ocho hospitales de la Secretaría de Salud, en el Occidente de la República Mexicana, que permite una evaluación detallada de los factores que contribuyen al riesgo de bajo peso. La mitad de las mujeres había dado a luz a recién nacidos de bajo peso (menos de 2.5 kgs) y el resto de peso normal. Este trabajo presenta los resultados de una serie de regresiones logísticas que estiman el riesgo de bajo peso al nacer. RESULTADOS: Los resultados indican que mientras los factores de comportamiento están asociados significativamente al bajo peso al nacer, los factores sociodemográficos y socioeconómicos están más relacionados con la utilización de servicios de atención prenatal. CONCLUSIONES: El papel clave de las características de comportamiento en la determinación del riesgo del bajo peso y el papel de los factores sociodemográficos y socioeconómicos en la determinación de atención prenatal, enfatizan la necesidad de incrementar la utilización de servicios de atención prenatal por parte de los sectores más desfavorecidos de la población.