Mothers' school starting age and infant health.

We study the effects of women's school starting age on the infant health of their offspring. In Spain, children born in December start school a year earlier than those born the following January, despite being essentially the same age. We follow a regression discontinuity design to compare the health at birth of the children of women born in January versus the previous December, using administrative, population-level data. We find small and insignificant effects on average weight at birth, but, compared to the children of December-born mothers, the children of January-born mothers are more likely to have very low birthweight. We then show that January-born women have the same educational attainment and the same partnership dynamics as December-born women. However, they finish school later and are (several months) older when they have their first child. Our results suggest that maternal age is a plausible mechanism behind our estimated impacts of school starting age on infant health.

Inequality in mortality between Black and White Americans by age, place, and cause and in comparison to Europe, 1990 to 2018.

Although there is a large gap between Black and White American life expectancies, the gap fell 48.9% between 1990 and 2018, mainly due to mortality declines among Black Americans. We examine age-specific mortality trends and racial gaps in life expectancy in high- and low-income US areas and with reference to six European countries. Inequalities in life expectancy are starker in the United States than in Europe. In 1990, White Americans and Europeans in high-income areas had similar overall life expectancy, while life expectancy for White Americans in low-income areas was lower. However, since then, even high-income White Americans have lost ground relative to Europeans. Meanwhile, the gap in life expectancy between Black Americans and Europeans decreased by 8.3%. Black American life expectancy increased more than White American life expectancy in all US areas, but improvements in lower-income areas had the greatest impact on the racial life expectancy gap. The causes that contributed the most to Black Americans' mortality reductions included cancer, homicide, HIV, and causes originating in the fetal or infant period. Life expectancy for both Black and White Americans plateaued or slightly declined after 2012, but this stalling was most evident among Black Americans even prior to the COVID-19 pandemic. If improvements had continued at the 1990 to 2012 rate, the racial gap in life expectancy would have closed by 2036. European life expectancy also stalled after 2014. Still, the comparison with Europe suggests that mortality rates of both Black and White Americans could fall much further across all ages and in both high-income and low-income areas.

Political instability and birth outcomes: Evidence from the 1981 military coup in Spain.

We study the effect of exposure to political instability in-utero on health at birth. We exploit the coup d'état that took place in Spain on February 23, 1981. Although short-lived and unsuccessful, the event generated stress and fear among the population, especially in areas that had suffered more repression during the Civil War and the recent dictatorship. We follow a difference-in-differences strategy and compare birth outcomes before and after the coup, in areas that were differentially "affected". We find that children who were in utero during the coup in more affected areas were born with significantly lower birth-weight (around 9 g lighter), especially if they were exposed to the coup in the first or second trimester of pregnancy. We contribute to the literature on the effects of maternal stress by focusing on an acute (and relatively common) source of distress that is unlikely to have affected newborn health via other channels.

Cash transfers before pregnancy and infant health.

We estimate the impact of a cash transfer targeting new mothers on their subsequent children's health outcomes at birth. We exploit the unexpected introduction of a generous, universal child benefit in Spain in 2007. Using population-wide, individual-level, high-quality administrative data from birth records and a regression discontinuity approach, we find that women who received the benefit were much less likely to have low-birth-weight children in the future (while their subsequent fertility was unaffected). The overall effect is driven by poor women, unmarried women, and women with low education, and by births taking place relatively soon after the benefit receipt. The €2500 transfer led to a 0.7 percentage-point decline in the fraction of children born under 1500 g in poorer households in the following five years, an 83% reduction. We explore the underlying channels, and find evidence supporting faster intrauterine growth, possibly driven by better maternal health, nutrition, and behaviors. Gestation length, family structure, and parental employment do not seem to play a role. Recent research suggests that targeting pregnant women may be more effective than later interventions (such as cash transfers to families with children), given the strong persistence of fetal health effects. Our results suggest that the impact may be stronger if women are targeted even earlier, before conception.

Newborn health and the business cycle: The role of birth order.

We use 35 years of administrative data to document how newborn health varies with the business cycle in Spain. In panel regressions that include province and year fixed effects as well as province trends, we show that children have significantly better health outcomes at birth in times of high unemployment: a 10 percentage-point increase in the unemployment rate is significantly associated with about 2 log-points higher birth-weight, almost 2 percentage points fewer babies with low birth weight, 0.6 points fewer babies with very low birth-weight, and a 0.4-point drop in mortality rates in the first 24 h We explore several potential mechanisms. First, we show that the documented association is not driven by in-utero selection: we do not find that high unemployment is associated with more miscarriages, abortions, or stillbirths. Second, we explore the role of composition in terms of parental characteristics. We find evidence that unmarried and younger parents, who typically have unhealthier babies, are relatively less likely to have children when unemployment is high. Finally, we show that there are fewer first births during recessions, and birth order is strongly positively correlated with health at birth. Birth order can account for up to one fifth of the countercyclicality of birth weight.

Sex selection and health at birth among Indian immigrants.

I use birth-certificate data for Spain to document extremely son-biased sex ratios at birth among Indian immigrants (122 boys per 100 girls), especially at higher parities. I also show that the children of Indian immigrants display poor health outcomes during infancy. For instance, almost 10% of boys with Indian parents are born prematurely, compared with 6% of boys with native parents. However, there is no evidence of a gender gap in infant health among the children of Indian immigrants. I provide evidence suggesting that the poor outcomes of Indian children at birth may be attributed to the low endowments of Indian mothers, while the absence of a gender gap may be driven by the fact that the parents who would invest less in girls are less likely to carry the pregnancies of girls to term (more likely to practice sex-selective abortion), combined with the lower cost of prenatal investments in Spain (compared with India).

Noncytopathic hepatitis A virus induces surface alterations in LLC-MK2 cells revealed by thin sections, negative staining, and scanning electron microscopy.

Previous electron microscope studies of ultrastructural events during hepatitis A virus replication in experimentally infected cells have used only ultrathin section techniques. Nevertheless, no important differences were observed between infected and uninfected cells. This study was carried out using scanning electron microscopy and negative staining of whole LLC-MK2 cells grown directly on grids covered with support membranes, and then infected with an hepatitis A virus strain. Thin sections of infected and uninfected controls were also analyzed. An intricate web of projections forming a net between cell interfaces was observed only in infected cells. Some of these projections were more than 700 nm long and had ballooning tips. Nevertheless, HAV particles were not visualized in the infected cells.

Noncytopathic hepatitis A virus induces surface alterations in LLC-MK2 cells revealed by thin sections, negative staining, and scanning electron microscopy

Previous electron microscope studies of ultrastructural events during hepatitis A virus replication in experimentally infected cells have used only ultrathin section techniques. Nevertheless, no important differences were observed between infected and uninfected cells. This study was carried out using scanning electron microscopy and negative staining of whole LLC-MK2 cells grown directly on grids covered with support membranes, and then infected with an hepatitis A virus strain. Thin sections of infected and uninfected controls were also analyzed. An intricate web of projections forming a net between cell interfaces was observed only in infected cells. Some of these projections were more than 700 nm long and had ballooning tips. Nevertheless, HAV particles were not visualized in the infected cells.