Florencia Torche

The Effect of Maternal Stress on Birth Outcomes: Exploiting a Natural Experiment

A growing body of research highlights that in utero conditions are consequential for individual outcomes throughout the life cycle, but research assessing causal processes is scarce. This article examines the effect of one such condition—prenatal maternal stress—on birth weight, an early outcome shown to affect cognitive, educational, and socioeconomic attainment later in life. Exploiting a major earthquake as a source of acute stress and using a difference-in-difference methodology, I find that maternal exposure to stress results in a significant decline in birth weight and an increase in the proportion of low birth weight. This effect is focused on the first trimester of gestation, and it is mediated by reduced gestational age rather than by factors affecting the intrauterine growth of term infants. The findings highlight the relevance of understanding the early emergence of unequal outcomes and of investing in maternal well-being since the onset of pregnancy.

Privatization Reform and Inequality of Educational Opportunity: The Case of Chile

Chile has experienced considerable educational expansion over the past few decades, as well as a privatization reform in 1981 that introduced full parental choice through a voucher system, in the context of a market-oriented transformation of the country. Using a cohort analysis of the 2001 Chilean Mobility Survey, this article examines trends in educational stratification in Chile over the past 50 years, with a focus on the changes that followed the privatization reform. The analysis shows that, in line with international findings, there is “persistent inequality” of educational opportunity across cohorts in Chile. Persistent inequality is not total, however. There is a small but significant increase in inequality in the transition to secondary education, which is cotemporaneous with the market-oriented transformation. Furthermore, when school sector-a form of “qualitative inequality” expressed in the distinction among public, private-voucher, and private-paid schools-is considered, the analysis suggests an increase in the advantages that are associated with private-voucher schools after the privatization reform, as well as in the benefits of attending private-paid schools during and after the reform. The article concludes by discussing the relationship among economic context, privatization reform, and educational inequality.

Unequal But Fluid: Social Mobility in Chile in Comparative Perspective

A major finding in comparative mobility research is the high similarity across countries and the lack of association between mobility and other national attributes, with one exception: higher inequality seems to be associated with lower mobility. Evidence for the mobility-inequality link is, however, inconclusive, largely because most mobility studies have been conducted in advanced countries with relatively similar levels of inequality. This article introduces Chile to the comparative project. As the 10th most unequal country in the world, Chile is an adjudicative case. If high inequality results in lower mobility, Chile should be significantly more rigid than its industrialized peers. This hypothesis is disproved by the analysis. Despite vast economic inequality, Chile is as fluid, if not more so, than the much more equal industrialized nations. Furthermore, there is no evidence of a decline in mobility as the result of the increase in inequality during the market-oriented transformation of the country in the 1970s and 1980s. Study of the specific mobility flows in Chile indicates a significant barrier to long-range downward mobility from the elite (signaling high “elite closure”), but very low barriers across nonelite classes. This particular mobility regime is explained by the pattern, not the level, of Chilean inequality-high concentration in the top income decile, but significantly less inequality across the rest of the class structure. The high Chilean mobility is, however, largely inconsequential, because it takes place among classes that share similar positions in the social hierarchy of resources and rewards. The article concludes by redefining the link between inequality and mobility.

Prenatal stress, gestational age and secondary sex ratio: the sex-specific effects of exposure to a natural disaster in early pregnancy

BACKGROUND Previous research suggests that maternal exposure to acute stress has a negative impact on the duration of pregnancy, and that this effect may vary by the time of exposure. It has also been proposed that stress exposure reduces the ratio of male-to-female births. To date, no study has jointly examined both outcomes, although they may be strongly related. Using population-level data with no selectivity, we jointly study the sex-specific effect of stress on the duration of pregnancy and the observed sex ratio among pregnant women exposed to a major earthquake in Chile. METHODS In a quasi-experimental design, women exposed to the earthquake in different months of gestation were compared with women pregnant 1 year earlier. Estimates from a comparison group of pregnant women living in areas not affected by the earthquake were also examined to rule out confounding trends. Regression models were used to measure the impact of earthquake exposure on gestational age and preterm birth by sex across month of gestation. A counterfactual simulation was implemented to assess the effect of the earthquake on the secondary sex ratio accounting for the differential impact of stress on gestational age by sex. RESULTS Earthquake exposure in Months 2 and 3 of gestation resulted in a significant decline in gestational age and increase in preterm delivery. Effects varied by sex, and were much larger for female than male pregnancies. Among females, the probability of preterm birth increased by 0.038 [95% confidence interval (CI): 0.005, 0.072] in Month 2 and by 0.039 (95% CI: 0.002, 0.075) in Month 3. Comparable increases for males were insignificant at the conventional P < 0.05 level. After accounting for the sex-specific impact on gestational age, a decline in the male-to-female ratio in Month 3 of exposure was detected [-0.058 (95% CI: -0.113, -0.003)]. CONCLUSIONS Maternal exposure to an exogenous stressor early but not late in the pregnancy affects gestational age and the probability of preterm birth. This effect is much stronger in females than males. Stress exposure in early pregnancy may also contribute to a decline in the ratio of male-to-female live births in exposed cohorts.

Educational Assortative Mating and Economic Inequality: A Comparative Analysis of Three Latin American Countries

Educational assortative mating and economic inequality are likely to be endogenously determined, but very little research exists on their empirical association. Using census data and log-linear and log-multiplicative methods, I compare the patterns of educational assortative mating in Brazil, Chile, and Mexico, and explore the association between marital sorting and earnings inequality across countries. The analysis finds substantial variation in the strength of specific barriers to educational intermarriage between countries, and a close association between these barriers and the earnings gaps across educational categories within countries. This finding suggests an isomorphism between assortative mating and economic inequality. Furthermore, educational marital sorting is remarkably symmetric across gender in spite of the different resources that men and women bring to the union. This study highlights the limitations of using single aggregate measures of spousal educational resemblance (such as the correlation coefficient between spouses’ schooling) to capture variation in assortative mating and its relationship with socioeconomic inequality.

Economic Crisis and Inequality of Educational Opportunity in Latin America.

Research in the industrialized world shows that the influence of family background on educational attainment has remained stable or declined over time. In contrast, very little is known about the developing world. Using high-quality data sets and a standard protocol, this article offers a comparative analysis of trends in educational stratification in four Latin American countries—Brazil, Chile, Colombia, and Mexico. Latin America provides an interesting case study because the economic crisis and structural adjustment in the 1980s led to declines in family income, which may have resulted in growing inequality of educational opportunity. Findings are consistent with this hypothesis. They show a marked increase in socioeconomic inequality at the secondary and postsecondary levels for the cohorts that experienced the economic crisis. In addition, there is a decline in inequality in the lower educational transitions, which is explained by their universalization, a reduced advantage of males, and in some cases a growing advantage of females.

Analyses of Intergenerational Mobility: An Interdisciplinary Review

This article reviews the sociological and economic literature on intergenerational mobility. Findings on social class, occupational status, earnings, and income mobility are discussed and discrepancies among them are evaluated. The review also examines nonlinearities in the intergenerational association, variation in mobility across advanced industrial countries, and recent mobility trends in the United States. The literature suggests an association between inequality and economic mobility at the country level, with the United States featuring higher inequality and lower mobility than other advanced industrial countries. However, mobility has not declined in the United States over the recent decades in which inequality has expanded. The inequality-mobility relationship fails to emerge when occupational measures of mobility are used, likely because these measures do not fully capture some mechanisms of economic reproduction.

Stability and Vulnerability of the Latin American Middle Class

Using panel data-sets from Mexico and Chile for the first years of the 21st century, the authors examine the determinants of middle-class intra-generational mobility. The middle class is defined by means of a latent index of economic well-being that is less sensitive to short-term fluctuation and measurement error than standard measures of income. The authors find high rates of both upward and downward mobility in Mexico and Chile, indicating that the middle class has opportunities to move to higher levels of well-being but is also vulnerable to falling into poverty. In both countries, labour-market resources (education and occupational status of the household head and number of members in the labour market) are much stronger determinants of mobility than demographic factors, suggesting the importance of policies that foster human capital and protect workers from shocks. Rural middle-class households are substantially more vulnerable to falling into poverty and have little chance of advancing to upper classes than their urban counterparts.

Intergenerational Influences of Wealth in Mexico

Using the 2006 Mexican Social Mobility Survey, this article evaluates the influence of parental wealth on several outcomes of adult children, including educational attainment, consumption level, asset holdings, home ownership, and home value. Three main findings emerge from the analysis. First, parental wealth is a strong determinant of educational attainment, net of the standard indicators of socioeconomic advantage. Furthermore, the influence of parental wealth appears to be stronger among the most disadvantaged children—those with low cultural capital residing in rural areas. Second, the mechanism of parental influence on adult children’s economic well-being differs depending on the outcome: in the case of consumption level, the influence is largely indirect, mediated by offspring’s human capital, while the opposite is true for children’s asset holdings, where a direct transfer of resources predominates. Third, access to homeownership is only weakly stratified by economic resources, but parental wealth significantly affects home value. The findings here highlight the critical but largely neglected impact of wealth on inequality and mobility in Latin America.

Seasonality of Birth Weight in Chile: Environmental and Socioeconomic Factors

PURPOSE Research suggests a relationship between birth weight and season of birth, but findings vary across countries and underlying factors are not well understood. We examine the seasonality of birth weight and explore alternative hypotheses for its etiology-exposure to environmental factors and varying socioeconomic composition of mothers-in Chile. METHODS Birth weight of approximately 5 million Chilean singleton live births 37 of 41 weeks of gestation between 1987 and 2007 were analyzed for seasonality by using regression models with month dummies and parametric sinusoidal specifications. Multivariate models with socioeconomic covariates and interactions across geographic regions examine potential factors accounting for seasonal variation. RESULTS Marked 12-month and 6-month periodic cycles were found. The amplitude and phase of the seasonal variation change across geographic regions. In the low-latitude northern region, there is a spring peak and a fall nadir, while in middle-latitude colder regions, a bimodal periodicity emerges with peaks in spring and fall, a pronounced winter nadir, and smaller nadir in the summer. Socioeconomic composition of mothers is found to vary with annual periodicity, but it does not account for the seasonality in birth weight. CONCLUSIONS Environmental factors rather than the socioeconomic composition of mothers likely account for seasonal variation in birth weight. The change in periodicity of birth weight across latitudes is consistent with a beneficial exposure to sunlight both early and late in the pregnancy, and a detrimental late exposure to cold temperatures only in areas with low winter temperatures.