ArticleInternational journal of epidemiology2019
Low birthweight and preterm birth: trends and inequalities in four population-based birth cohorts in Pelotas, Brazil, 1982-2015.
Article in International journal of epidemiology, 2019. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 33 papers.
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33 citing papers in PubMed.
- Sociodemographic, Behavioral and Oral Health Factors in Maternal and Child Health: An Interventional and Associative Study from the Network Perspective.International journal of environmental research and public health · 2021Trial
- Examining pathways between trajectories of maternal depressive symptoms, harsh parenting, and adolescent executive functions: insights from the 2004 Pelotas birth cohort.European child & adolescent psychiatry · 2026Article
- Concordance Between Estimated Fetal Weight by Ultrasound and Birth Weight and Its Association with Adverse Perinatal Outcomes.Journal of clinical medicine · 2025Article
- Use of modern contraceptive methods and pregnancy planning: a cohort study.Revista de saude publica · 2025Article
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- Ethno-racial inequalities on adverse birth and neonatal outcomes: a nationwide, retrospective cohort study of 21 million Brazilian newborns.Lancet regional health. Americas · 2024Article
- Associations Among Birth Weight, Adrenarche, Brain Morphometry, and Cognitive Function in Preterm Children Ages 9 to 11 Years.Biological psychiatry. Cognitive neuroscience and neuroimaging · 2024Article
- Maternal Exposure to Potentially Toxic Metals and Birth Weight: Preliminary Results from the DSAN-12M Birth Cohort in the Recôncavo Baiano, Brazil.International journal of environmental research and public health · 2023Article
- Contextual, maternal, and infant factors in preventable infant deaths: a statewide ecological and cross-sectional study in Rio Grande do SUL, Brazil.BMC public health · 2023Article
- Association of perinatal factors with suspected developmental delay in urban children aged 1-36 months - a large-scale cross-sectional study in China.BMC pediatrics · 2023Article
- Association between preterm births and socioeconomic development: analysis of national data.BMC public health · 2022Observational
- Adverse pregnancy and perinatal outcomes in Latin America and the Caribbean: systematic review and meta-analysis.Revista panamericana de salud publica = Pan American journal of public health · 2022Review
- Prospective cohort study of children exposed to hepatitis C virus through a pregnancy screening program.International journal of infectious diseases : IJID : official publication of the International Society for Infectious Diseases · 2021Article
- Maternal and neonatal factors associated with child development in Ceará, Brazil: a population-based study.BMC pediatrics · 2021Article
- Impact of gestational hypertension and preeclampsia on low birthweight and small-for-gestational-age infants in China: A large prospective cohort study.Journal of clinical hypertension (Greenwich, Conn.) · 2021Article
- Prematurity and body composition at 6, 18, and 30 years of age: Pelotas (Brazil) 2004, 1993, and 1982 birth cohorts.BMC public health · 2021Article
- Evolution of care during pregnancy and childbirth in the extreme south of Brazil.Revista de saude publica · 2021Article
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- The preterm social brain: altered functional networks for Theory of Mind in very preterm children.Brain communications · 2021Article
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Abstract
backgroundDespite positive changes in most maternal risk factors in Brazil, previous studies did not show reductions in preterm birth and low birthweight. We analysed trends and inequalities in these outcomes over a 33-year period in a Brazilian city.
methodsFour population-based birth cohort studies were carried out in the city of Pelotas in 1982, 1993, 2004 and 2015, with samples ranging from 4231 to 5914 liveborn children. Low birthweight (LBW) was defined as <2500 g, and preterm birth as less than 37 weeks of gestation. Information was collected on family income, maternal skin colour and other risk factors for low birthweight. Multivariable linear regression was used to estimate the contribution of risk factors to time trends in birthweight.
resultsPreterm births increased from 5.8% (1982) to 13.8% (2015), and LBW prevalence increased from 9.0% to 10.1%, being higher for boys and for children born to mothers with low income and brown or black skin colour. Mean birthweight remained stable, around 3200 g, but increased from 3058 to 3146 g in the poorest quintile and decreased from 3307 to 3227 g in the richest quintile. After adjustment for risk factors for LBW, mean birthweight was estimated to have declined by 160 g over 1982-2015 (reductions of 103 g in the poorest and 213 g in the richest quintiles).
conclusionsData from four birth cohorts show that preterm births increased markedly. Mean birthweights remained stable over a 33-year period. Increased prevalence of preterm and early term births, associated with high levels of obstetric interventions, has offset the expected improvements due to reduction in risk factors for low birthweight.
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