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 impact of breast feeding patterns on the biometric analysis of infant mortality

A major assumption of the biometric analysis of infant mortality as developed by Bourgeois-Pichat is that the age structure of infant deaths after the first month of life is virtually constant across time and cultures. Reanalysis of results from studies which compare the mortality of infants according to the type of feeding indicated that the relationship between mortality and age within the first year of life followed different patterns for breast fed and artificially fed infants. Historical data for populations with different breast feeding customs reveal similar differences in the age pattern of infant mortality. In populations where breast feeding was uncommon or of very short duration, infant mortality rises particularly steeply during the early months of the first year of life. The age structure of infant mortality in less developed countries where breast feeding is decreasing rapidly may be similarly affected. When substantial deviations from the linear relationship are evident, particular caution is required in applying the biometric technique, since in such situations the estimated endogenous mortality is very much affected by the particular set of data points within the first year of life which are chosen for the basis of the estimates.     

The Differential Mortality of Undesired Infants in Sub-Saharan Africa

With high rates of infant mortality in sub-Saharan Africa, investments in infant health are subject to tough prioritizations within the household, in which maternal preferences may play a part. How these preferences will affect infant mortality as African women have ever-lower fertility is still uncertain, as increased female empowerment and increased difficulty in achieving a desired gender composition within a smaller family pull in potentially different directions. I study how being born at a parity or of a gender undesired by the mother relates to infant mortality in sub-Saharan Africa and how such differential mortality varies between women at different stages of the demographic transition. Using data from 79 Demographic and Health Surveys, I find that a child being undesired according to the mother is associated with a differential mortality that is not due to constant maternal factors, family composition, or factors that are correlated with maternal preferences and vary continuously across siblings. As a share of overall infant mortality, the excess mortality of undesired children amounts to 3.3 % of male and 4 % of female infant mortality. Undesiredness can explain a larger share of infant mortality among mothers with lower fertility desires and a larger share of female than male infant mortality for children of women who desire 1–3 children. Undesired gender composition is more important for infant mortality than undesired childbearing and may also lead couples to increase family size beyond the maternal desire, in which case infants of the surplus gender are particularly vulnerable.     

Paradox Revisited: A Further Investigation of Racial/Ethnic Differences in Infant Mortality by Maternal Age

I reexamine the epidemiological paradox of lower overall infant mortality rates in the Mexican-origin population relative to U.S.-born non-Hispanic whites using the 1995–2002 U.S. NCHS linked cohort birth-infant death files. A comparison of infant mortality rates among U.S.-born non-Hispanic white and Mexican-origin mothers by maternal age reveals an infant survival advantage at younger maternal ages when compared with non-Hispanic whites, which is consistent with the Hispanic infant mortality paradox. However, this is accompanied by higher infant mortality at older ages for Mexican-origin women, which is consistent with the weathering framework. These patterns vary by nativity of the mother and do not change when rates are adjusted for risk factors. The relative infant survival disadvantage among Mexican-origin infants born to older mothers may be attributed to differences in the socioeconomic attributes of U.S.-born non-Hispanic white and Mexican-origin women.     

Registration completeness and international comparisons of infant mortality

The physical development of the live born infant is the single most important variable governing its survival: infant mortality among those weighing 2,500 grams (5 1/2 pounds) or less at birth is 17 times the mortality among those weighing more than 2,500 grams at birth. The variation in mortality according to birth weight (or gestation) is greater than for subclasses of color, sex, maternal age, or birth order. Infant mortality in the United States is significantly higher than in a number of other countries e.g., Sweden, Netherlands, Norway. The difference is thought, by some, to be due to underregistration of low birth weight infants in other countries. In this paper, distributions of live births by birth weight for Denmark, England and Wales, New Zealand, and the United States, and infant mortality data for Denmark and the United States are examined. The data do not support a hypothesis of gross underregistration of live born infants in other countries. The results indicate that some index of physical development (birth weight, gestation, or a combination of both) should be included in any appraisal of infant mortality.     

Spanish Surname and Anglo Infant Mortality: Differentials Over a Half-Century

Using a half-century of death records from San Antonio/Bexar County, Texas, we examine the timing and cause structure of Spanish surname and Anglo infant mortality. Our findings show that despite the substantial disparities between ethnic-specific infant mortality rates in the early years of the study, there have been consistent declines in overall, neonatal, and postneonatal mortality for both groups, as well as a major convergence of mortality rates between Spanish surname and Anglo infants. Further, we demonstrate that the convergence is of relatively recent origin and is due primarily to shifts in postneonatal mortality. Finally, we examine the transition reflected in the cause structure of ethnic-specific infant mortality and show that the convergence was largely the result of reductions in deaths from exogenous causes. Implications for research into the "epidemiologic paradox" are discussed.     

Infant mortality and fertility in three Bavarian villages: An analysis of family histories from the 19th century

Abstract Family history data derived from the records of three parishes in Bavaria provide evidence for several important demographic questions when analysed in conjunction with information concerning the prevalent breast-feeding practices. The results suggest strongly that breast feeding can prolong birth intervals substantially. The evidence concerning the independent influence of infant deaths on subsequent birth intervals is inconclusive. It is clear, however, that even if such an influence did exist it was relatively small, compared to the effect of lactation. In addition the results do not lend support to the hypothesis that couples experiencing low child mortality practised family limitation more than couples experiencing high child mortality. In all three parishes, however, fertility appeared to influence infant mortality. Infants born after short intervals were subject to considerably higher mortality risks than infants following longer intervals.     

The estimation of mortality at the London Foundling Hospital, 1741-99

The high mortality of foundlings across Europe has long been established by historical demographers but methods of quantification have not permitted comparison with rates in the populations beyond the foundling hospitals. This study investigates mortality rates at the London Foundling Hospital in the eighteenth century in a way that addresses the issue. The study finds that although foundling mortality was extremely high at certain periods in the hospital's history, there is evidence for a decline towards the end of the century, in common with national and local rates. This suggests that the causes of the mortality fall were common even to infants born in disadvantaged circumstances, and brought up away from their mothers. Several possible reasons for the fall in mortality are considered, including improved nutrition among mothers, a shift in the disease environment, and changes in such habits as gin drinking.     

Race/Ethnicity/Nativity Differentials and Changes in Cause-Specific Infant Deaths in the Context of Declining Infant Mortality in the U.S.: 1989–2001

Using data from the national linked birth/infant death cohort files, we examined race/ethnicity/nativity disparities and changes in infant mortality due to the five leading causes of infant death between 1989 and 2001. Our results indicate substantial decreases in infant mortality from three causes (congenital anomalies, sudden infant death syndrome, and respiratory distress syndrome) for which specific perinatal health innovations emerged or were expanded. However, for these three causes, the relative disparities in infant mortality between infants born to U.S.-born black women as compared to infants of U.S.-born white women increased following the introduction (or expansion) of beneficial interventions. Among infants of U.S.-born Mexican American mothers, the findings differed. In the static comparisons, our results show the often-reported similarity in the risk of death of these babies compared to those born to non-Hispanic white mothers. However, when changes over time were modeled, there was an erosion of the relatively favorable survival chances of Mexican American infants. Our models show little change in the relative risk of death for infants of immigrant women. Regarding the other two causes (disorders relating to short gestation and unspecified low birth weight and maternal complications) for which no efficacious innovations occurred, either little change or actual increases in risks were observed. Future studies and health policy efforts should be geared toward further understanding and aggressively working to close infant mortality gaps, especially for infants of U.S.-born black mothers—an effort that will be facilitated by research focused on cause-specific infant mortality.     

Mortality in New Zealand and England and Wales

This paper compares age-specific mortality rates in England and Wales with those of New Zealand. Differences in rates are greatest at the younger age groups, and are particularly high for infants under 1 year and children between 1 and 5 years. The age-specific mortality rates for females under 25 years and for males under 35 years are analysed by causes of death in order to discover where the main differences between the two countries occur, and for infant mortality in England and Wales a further analysis has been made by social class. The greatest room for improvement in England and Wales mortality rates, as compared with New Zealand rates, is at ages under 5 years, and in infant mortality in particular the greatest differences between England and Wales and New Zealand rates by causes of death are for those causes usually associated with environmental influences.     

Respiratory illness in Saskatoon infants: The impact of housing and neighbourhood characteristics

Respiratory illness is an important childhood illness and a significant cause of infant mortality. This study examined the relationship between neighbourhood level variables and rates of respiratory illness for children less than 2 years of age, born in Saskatoon between 1992 and 1994. Rates of respiratory illness, as measured by proportion of children hospitalized and frequency of hospitalization and ambulatory visits to physicians, were higher among infants living in socially disadvantaged neighbourhoods. Multivariate predictive models for rates of respiratory illness support the research hypothesis that housing characteristics, in the presence of other neighbourhood characteristics, have a significant impact on determining the rates of respiratory illness among Saskatoon children.     

Bridging the gap: Determining long-term changes in infant mortality in pre-registration England and Wales

Much effort has been expended in analysing a small sample of parish registers to produce national estimates of infant mortality for the period 1570–1840. However, in an age when inter-parish variations in infant mortality were considerable, national trends often obscured local and regional differences. By analysing data from the initial years of Civil Registration (1839–1846) together with infant mortality rates from a range of parishes, it is possible to assess the extent of variation and change in England and Wales during the period 1580–1840. The geographical variations in infant mortality and the age structure of infant deaths were sufficient to suggest that the most important influence on whether infants survived was disease environments.     

Absolute Change in Cause-Specific Infant Mortality for Blacks and Whites in the US: 1983–2002

This paper examines absolute change in infant mortality from 5 leading causes of death for whites and blacks over a 20 year period. Change in infant mortality varies by cause, race, and birth weight. Absolute decline in mortality from respiratory distress syndrome (RDS) and sudden infant death syndrome (SIDS) in the overall study population has been more rapid for black infants during the period after specific technological innovations were approved and behavioral practices were recommended for these conditions. For low birth weight infants, blacks experienced greater decline in mortality from SIDS and whites experienced greater decline in RDS mortality. Despite remarkable declines in mortality from these causes, relative racial disparities have increased over this time period. For the overall study population, blacks and whites experienced similar rates of mortality decline from congenital anomalies. Mortality decline from this cause among low birth weight infants occurred at a faster pace for whites. Mortality from causes for which no specific innovations were developed increased for blacks but remained relatively constant for whites. An analysis of absolute change complements the relative disparities approach by revealing the dynamics of change, thus providing a more complete understanding of changing racial disparities in infant mortality.     

Direct and indirect effects on infant mortality in a high-fertility US population

This article examines the direct and indirect effects of social and demographic measures on infant mortality using data from a church directory of the Old Order Amish of the Lancaster, PA, Settlement. The sample includes all infant deaths and a simple random sample of survivors (total n=2013). The results reveal that the death of the immediately prior sibling directly increases the risk of infant death nearly 30%, net of other factors. Also, the risk of mortality in the first year increases as birth order increases, particularly at the highest orders (8–17 prior sibs). Infants of the youngest mothers (age 13) are nearly 10% more likely to die in the first year of life than are infants of mothers age 24, nearly all of which is indirect via parity, prior sib death and birth interval. Further analysis shows that families adapting more rapidly to external community pressures face a higher risk of infant death than families living in more stable areas. These relationships emerge even in this homogeneous population with a relatively high standard of living and a traditional lifestyle, Implications are that indirect effects should be included in research on teen pregnancy and infant survival, and might be especially important for studies in transitional geographic areas.An earlier version of this paper was presented at the 1993 meetings of Population Association of America, Cincinnati.     

The contribution of medical measures to the decline of mortality from respiratory tuberculosis: An ageperiod-cohort model

The decline of mortality in the more developed nations has been related to two major influences, economic development and the introduction of medical measures. The contribution of medical measures has been a source of continuing controversy. Most previous studies employ either a birth cohort or calendar year arrangement of mortality data to address this controversy. The present study applies an age-period-cohort model to mortality from respiratory tuberculosis in England and Wales, Italy, and New Zealand in an attempt to separate economic influences from that of medical measures. The results of the analysis indicate that while the overall contribution of medical measures is small when examined by calendar year, specific birth cohorts both in Italy and in England and Wales benefited substantially from these measures. The environmental conditions in New Zealand, however, were such that the introduction of medical measures barely affected declining mortality levels from respiratory tuberculosis.     

Infant mortality decline in Chile: A replication

This replication of a previous analysis of the effect of sociological variables on infant mortality rates in Chile refines the earlier work by using the more numerous communes for comparisons, by presenting the basic data in the form of a path analysis, and by expanding the theory to include “health practices,” customs, such as avoiding teenage pregnancies, that are community-backed and maintained. This type of practice is then integrated into the “institutionalized problem-solving capacity” framework that guides the analysis. Urabnization and voting, the two indicators of institutionalized problem-solving capacity, predict reduced infant morality, as before. Teen pregnancies is a positive predictor, as expected, but the number of children already born does not predict. These results are net of two indicators of health technology-whether or not a physician was in attendance, and the number of clinics. Mother's education also predicted low infant morality, and the theory is applied to this well-known predictor to interpret its effect. In addition, the anomalous role of mother's education in the dominant biomedical explanation is highlighted.     

Apostles and Zionists: the influence of religion on demographic change in rural Zimbabwe

Religion has acted as a brake on demographic transition in a number of historical and contemporary populations. In a study in two rural areas of Zimbabwe, we found substantial differences in recent demographic trends between Mission and Independent or "Spirit-type" churches. Birth rates are higher in some Spirit-type churches and, until recently, infant mortality was also higher. Recent increases in mortality were seen within Mission churches but not in Spirit-type churches. Missiological and ethnographic data indicate that differences in religious teaching on healthcare-seeking and sexual behaviour and differences in church regulation could explain this contrast in demographic patterns. More restrictive norms on alcohol consumption and extra-marital relationships in Spirit-type churches may limit the spread of HIV and thereby reduce its impact on mortality. These contrasting trends will influence the future religious and demographic profile of rural populations in Zimbabwe.     

Comparative analysis of the index of our population life quality]

A comprehensive method of calculating and measuring a country's or an area's health and literacy levels is examined. The method, known as population quality life inference (PQLI), was used to determine which of China's provinces has the highest and the lowest degree of population quality. The PQLI indicates infant mortality, average life expectancy of 1 year olds, and literacy rates of those 15 years and older. Because developing countries traditionally have high rates of infant mortality and illiteracy and low life expectancy rates during their industrialization, measuring the degree of population quality of life improvement of such countries during this period was found to be significant. These factors (infant mortality, illiteracy, and life expectancy) will improve substantially as industrialization continues. In order to compare various areas, these 3 factors must be changed into "inferences" 0-100, "0" representing the lowest population quality and "100" the highest. These 3 inferences must then be averaged in order to calculate the PQLI. For example: life expectancy value 77 (highest in the world) minus 38 (lowest)/100 = .39. In order to measure the value of India's life expectancy: value of 1-year-old's life expectancy = 56 (1-year-old's life expectancy in India) minus 38/.39 = 46. The value of adult illiteracy does not need to be changed. Thus, the actual comparison will be based on the values of the 3 inferences. Using this method of calculation, it is concluded that the PQLI analysis indicated that Peking (93.04) is the highest in China and Yumnan Province (60.72) is the lowest.