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Background Preterm very-low-birth-weight (PT-VLBW) infants are at risk of an elevated systolic blood pressure (SBP) in infancy and adulthood; however, the pathogenesis remains unclear. Altered renal development or function may be associated with increased SBP, but their contribution in PTVLBW is unknown. Methods We determined renal function and its relationship to SBP in three groups of PT-VLBW at 1, 2, and 3 years of age, using serum cystatin-C to calculate the estimated glomerular filtration rate (eGFR). Results Cystatin-C levels decreased from 0.84 ± 0.2 (SD) within the 1-year group to 0.70 ± 0.1 mg/l (± SD; P Conclusions Preterm very-low-birth-weight infants demonstrate increasing renal function with advancing age. An elevated SBP and eGFR at 1 year suggests dysfunctional renal autoregulation and hyperfiltration, which may alter subsequent renal function and contribute to the lower eGFR seen at 3 years in infants with the lowest birth weight and gestational age. Keywords Glomerular filtration rate * Cystatin-C * Renal development * Developmental programming * Developmental plasticity, Introduction Barker and colleagues pioneered the concept that environmental factors, particularly abnormal fetal nutrition, program the risk of cardiovascular disease, hypertension (HTN), type 2 diabetes, obesity, and chronic kidney disease [...]

Maternal perturbations or sub-optimal conditions during development are now recognized as contributing to the onset of many diseases manifesting in adulthood. This 'developmental programming' of disease has been explored using animal models allowing insights into the potential mechanisms involved. Impaired renal development, resulting in a low nephron number, has been identified as a common outcome that is likely to contribute to the development of hypertension in the offspring as adults. Changes in other organs and systems, including the heart and the hypothalamic-pituitary-adrenal axis, have also been found. Evidence has recently emerged suggesting that epigenetic changes may occur as a result of developmental programming and result in permanent changes in the expression patterns of particular genes. Such epigenetic modifications may be responsible not only for an increased susceptibility to disease for an individual, but indirectly for the establishment of a disease state in a subsequent generation. Further research in this field, particularly examination as to whether epigenetic changes to genes affecting kidney development do occur, are essential to understanding the underlying mechanisms of developmental programming of disease. Keywords Kidney* Glucocorticoids* Prenatal programming * Epigenetic modification, Introduction Hypertension is a major risk factor for the development of cardiovascular disease (CVD) and a common complication of other metabolic disorders, such as obesity and type-2 diabetes. These chronic [...]

This study investigates the geography of racial disparities in low birthweight in New York City by focusing on racial residential segregation and its effect on the risk of low birthweight among African-American infants and mothers. This cross-sectional multilevel analysis uses birth records at the individual level (n = 96,882) and racial isolation indices at the census tract or neighborhood level (n = 2095) to measure their independent and cross-level effects on low birthweight. This study found that residential segregation and neighborhood poverty operate at different scales to increase the risk of low birthweight. At the neighborhood scale residential segregation is positively and significantly associated with low birthweight, after controlling for individual-level risk factors and neighborhood poverty. Residential segregation explains neighborhood variation in low birthweight means and race effects across census tracts, which cannot be accounted for by neighborhood poverty alone. At the individual scale-increasing levels of residential segregation does not significantly reduce or exacerbate individual-level risk factors for low birthweight; whereas increasing levels of neighborhood poverty significantly eliminates the race effect and reduces the protective effect of being foreign-born on low birthweight, after controlling for other individual-level risk factors and residential segregation. These findings are contradictory to previous health research that shows protective mechanisms associated with ethnic density in local areas. It is likely that structural factors underlying residential segregation, i.e., racial isolation, impose additional stressors on African-American women that may offset or disguise positive attributes associated with ethnic density. However, as poverty is concentrated within these neighborhoods, differences between races in low birthweight cease to exist. This study demonstrates that residential segregation and neighborhood poverty are important determinants of racial disparity in low birthweight in New York City. Keywords: Racial disparities; Birthweight; Residential segregation; Multilevel modelling; African-American; USA

Objectives: To assess the characteristics of Indigenous births and to examine the risk factors for preterm ( Design: Prospective cohort of singleton births to women attending Townsville Aboriginal and Islander Health Services (TAIHS) for shared antenatal care between 1 January 2000 and 31 December 2003. Main outcome measures: Demographic, obstetric, and antenatal care characteristics are described. Risk factors for preterm birth, low birth weight and SGA births are assessed. Results: The mean age of the mothers was 25.0 years (95% CI 24.5-25.5), 15.8% reported hazardous or harmful alcohol use, 15.1% domestic violence, 30% had an inter-pregnancy interval of less than 12 months and 9.2% an unwanted pregnancy. The prevalence of infection was 50.2%. Predictors of preterm birth were a previous preterm birth, low body mass index (BMI) and inadequate antenatal care, with the subgroup at greatest risk of preterm birth being women with a previous preterm birth and infection in the current pregnancy. Predictors of a low birth weight birth were a previous stillbirth, low BMI and an interaction of urine infection and non-Townsville residence; predictors of an SGA birth were tobacco use, pregnancy-induced hypertension and interaction of urine infection and harmful alcohol use. Conclusion: The prevalence of demographic and clinical risk factors is high in this group of urban Indigenous women. Strategies addressing potentially modifiable risk factors should be an important focus of antenatal care delivery to Indigenous women and may represent an opportunity to improve perinatal outcome in Indigenous communities in Australia.

This study investigates the relationship between maternal skin tone and low birth weight among Puerto Ricans, a group with a complex ancestry and skin tones that range from very light to very dark. Using data from a representative sample of Puerto Rican mothers, we assess whether skin tone has different implications for low birth weight in three geographic areas (Puerto Rico; New York City; other eastern states). The analysis shows that skin tone is unrelated to low birth weight in Puerto Rico and New York City. However, in the other eastern states in our sample, mothers with dark skin have a high risk of bearing a low birth-weight infant, relative to mothers with light skin. We interpret our findings in light of differences in the social meaning of phenotypic differences across locales. Keywords: Infant health; Skin tone; Puerto Rico; USA

Individual-level maternal risk factors have been able to explain only a small proportion of low birth weight (LBW) births in the US to date and neighborhood-level factors have not been recognized as important predictors of reproductive outcomes. At the US/Mexico border, tremendous demographic changes have taken place between 1980 and 1990. Whether high population growth, economic pressures, and community instability have affected reproductive health in this region is not known. We used spatial epidemiologic methods to investigate the importance of changes in neighborhood and individual-level risk factors in predicting changes in two measures of adverse reproductive health: term and preterm LBW. Using approximately 16,000 births in 1980 and 24,000 births in 1990, we produced a continuous surface of LBW change (Z scores for difference in proportions) for southern San Diego County, CA, and identified statistically significant 'hot spots' of elevated risk. Using a geographic information system, data from the 1980 and 1990 US Census were smoothed to link neighborhood-level variables with individual-level data from the 1980 and 1990 California birth certificates. Multivariate regression models were developed to identify individual- and neighborhood-level variables of 1980-1990 changes which were predictive of Z scores of LBW change. Results of conditional autoregressive models were used to assess effects of spatial autocorrelation. The continuous surface of LBW identified areas with statistically significant increases (17) areas for term LBW and 14 areas for preterm LBW). While individual- and neighborhood-level variables explained about an equal amount of variance in term LBW, only neighborhood-level variables were significant predictors of preterm LBW. While changes in maternal race/ethnicity composition and a measure of stability were related to term LBW, measures of affluence were related to preterm LBW. This study highlights the importance of socioeconomic and demographic changes in a woman's neighborhood on reproductive health. Keywords: Low birth weight; Spatial methods; Epidemiology; Reproductive health; San Diego county; Neighborhood level factors; USA

[G30] TRANSIENT ADRENOCORTICAL INSUFFICIENCY OF PREMATURITY (TAP) AND SYSTEMIC HYPOTENSION IN VERY LOW BIRTH WEIGHT INFANTS P.C. Ng, C.H. Lee, C.W.K. Lam, K.C. Ma, T.F. Fok, I.H.S. Chan, E. Wang. [...]

This article reviews recent medical research on the relationship between young maternal age and the incidence of low birth weight infants. One line of research, 'nature,' emphasizes biological factors in early adolescence such as immaturity of the female reproductive system and inadequate prenatal weight gain. 'Nurture,' another research focus, stresses sociocultural attributes of teen mothers such as poverty and minority status. Young maternal age alone does not explain the higher rates of low birth weight infants born to adolescent females. Both biological and sociocultural factors, plus lifestyle choices made by adolescents, combine to raise or lower the risk of delivering a low birth weight infant. School health personnel need to link their health promotion efforts to those of other community organizations serving adolescents and their families. (J Sch Health. 1998;68(7):271-275), Medical research investigating the association between young maternal age and the incidence of low birth weight babies has implications for school health personnel. Adolescent females are two times more likely [...]

Problems in determining gestational age of Aboriginal babies with low birthweight are discussed. Topics include low birthweight pattern, effect of misclassification of gestational age, and the need to determine modifiable risk factors for preterm birth.