BackgroundYoung maternal age has long been associated with higher infant mortality rates, but the role of socioeconomic factors in this association has been controversial. We sought to investigate the relationships between infant mortality (distinguishing neonatal from post-neonatal deaths), socioeconomic status and maternal age in a large, retrospective cohort study.MethodsWe conducted a population-based cohort study using linked birth-death certificate data for Missouri residents during 1997–1999. Infant mortality rates for all singleton births to adolescent women (12–17 years, n = 10,131; 18–19 years, n = 18,954) were compared to those for older women (20–35 years, n = 28,899). Logistic regression was used to estimate adjusted odds ratios (OR) and 95% confidence intervals (CI) for all potential associations.ResultsThe risk of infant (OR 1.95, CI 1.54–2.48), neonatal (1.69, 1.24–2.31) and post-neonatal mortality (2.47, 1.70–3.59) were significantly higher for younger adolescent (12–17 years) than older (20–34 years) mothers. After adjusting for race, marital status, age-appropriate education level, parity, smoking status, prenatal care utilization, and poverty status (indicated by participation in WIC, food stamps or Medicaid), the risk of post-neonatal mortality (1.73, 1.14–2.64) but not neonatal mortality (1.43, 0.98–2.08) remained significant for younger adolescent mothers. There were no differences in neonatal or post-neonatal mortality risks for older adolescent (18–19 years) mothers.ConclusionSocioeconomic factors may largely explain the increased neonatal mortality risk among younger adolescent mothers but not the increase in post-neonatal mortality risk.

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Objective: The association between air pollution and the prevalence of overweight and obesity is evaluated. Methods: The population consisted of 30,056 children (aged 2-14 years), randomly selected from 25 districts in Northeast China. Child weight and height were measured, and exposures to particulate matter with an aerodynamic diameter 10 lm (PM 10 ), sulfur dioxide (SO 2 ), nitrogen dioxides (NO 2 ), and Ozone (O 3 ) were estimated from the data collected at monitoring stations in the 25 districts. Using two-level logistic models, we examined the association between the exposure and the prevalence of overweight and obesity. Results: Among the study children, 12.3% (3,704) were overweight and 14.1% (4,233) were obese. After adjusting for confounding factors, an increased prevalence of obesity was associated with an interquartile range increase in PM 10 (31 lg/m 3 ; odds ratio [ORs] ¼ 1.19; 95% confidence interval [CI]: 1.11-1.26), SO 2 (7.4 ppb; ORs ¼ 1.11; 95% CI: 1.03-1.20), NO 2 (5.3 ppb; ORs ¼ 1.13; 95% CI: 1.04-1.22), and O 3 (11.5 ppb; ORs ¼ 1.14; 95% CI: 1.04-1.24). Prevalence of overweight increased with an interquartile range increase in O 3 (11.5 ppb; ORs ¼ 1.09; 95% CI: 1.03-1.15). Conclusions: This study suggests that air pollution is positively associated with an increased likelihood of obesity or overweight in children.

An understanding of the relationship between psychiatric disorders and menstrual characteristics is important to the assessment and care of women. Menstrual cycle regularity and length have significant associations with specific current and lifetime psychiatric disorders. The purpose of this study was to investigate whether psychiatric disorders are associated with menstrual cycle length or regularity. The sample included 628 pregnant Medicaid-eligible women from Women, Infants and Children Supplemental Nutrition Program sites in 5 counties in rural Missouri and the city of St. Louis. Women were assessed for current (12-month) and lifetime psychiatric disorders with the Diagnostic Interview Schedule IV. Menstrual length and regularity were assessed by self-report. Analyses consisted of logistic regression while controlling for race.