Prematurity is a leading cause of neonatal mortality and a global health problem that affects high, middle and low-income countries. Several factors may increase the risk of preterm birth. In this article, we test the hypothesis that different risk factors determine preterm birth in different income groups by investigating whether risk factors for preterm deliveries in the 2004 Pelotas (Rio Gra...

BACKGROUND Women in New York State are heavily affected by the human immunodeficiency virus (HIV) epidemic. New York has had the largest number of births to HIV-infected pregnant women in the United States. Data collected as part of the Survey of Childbearing Women have been valuable for assessing the impact of the disease on the women of New York. OBJECTIVE To assess HIV prevalence trends am...

BACKGROUND Birthweight is associated with cognition and educational attainment across the full birthweight range in the normal population, independently of social background. However, the extent to which birthweight reflects fetal growth, or is a marker of subsequent size, with respect to this association, is not clear. We therefore investigated the independent effects of birthweight and postna...

Survival in type 1 diabetes has improved, but the impact on life expectancy in the U.S. type 1 diabetes population is not well established. Our objective was to estimate the life expectancy of the Pittsburgh Epidemiology of Diabetes Complications (EDC) study cohort and quantify improvements by comparing two subcohorts based on year of diabetes diagnosis (1950-1964 [n = 390] vs. 1965-1980 [n = 5...

Given the growing recognition of the importance of the life course approach for the determination of chronic diseases, birth cohort studies are becoming increasingly important. This paper describes the methods used in the 1982 Pelotas (Brazil) birth cohort study, one of the largest and longest studies of this type in developing countries. All 5,914 hospital births occurring in Pelotas in 1982 (...

OBJECTIVE To use a case-control study to analyze risk factors associated with teenage childbearing among adolescents who were in a birth cohort study that began in 1982 in the city of Pelotas, Rio Grande do Sul, Brazil. METHODS Adolescent mothers in Pelotas who gave birth between January 1995 and March 2001 and who had been born in 1982 were identified through the local birth information syst...

OBJECTIVE To analyze economic inequality (absolute and relative) due to family income in relation to the occurrence of preterm births in Southern Brazil. METHODS Four birth cohort studies were conducted in the years 1982, 1993, 2004, and 2011. The main exposure was monthly family income and the primary outcome was preterm birth. The inequalities were calculated using the slope index of inequa...

OBJECTIVE Season of birth has repeatedly been found to be a risk indicator for adverse neurodevelopmental outcomes. Several explanations for this finding have been put forward but no conclusion has been reached. In the current study, we explored the role of sociodemographic and biological factors in the association between season of birth and child IQ. DESIGN In a prenatally recruited birth c...

OBJECTIVES This study examines the influence of socioeconomic circumstances in childhood (childhood SES) and adulthood (adult SES) on timing of first birth by age 37. METHODS A longitudinal study of a 1972-1973 New Zealand birth cohort collected information on socioeconomic characteristics from age 3-32 and reproductive histories at 21, 26, 32 and 38; information on first birth was available ...

STUDY OBJECTIVE The aim was to describe rates of loss and assessment of representativeness during 43 years of a national birth cohort study. DESIGN The study population is a class stratified random sample of all single, legitimate births that occurred during one single week in 1946; it has been studied at regular intervals, so far to 1989. MAIN RESULTS Losses through death and emigration we...