RESUMEN
Socio-economic disadvantage is usually associated with low birthweight (LBW). However, it has been shown that Mexican Americans, despite being economically less advantaged, present LBW rates that are similar to or lower than those found among white women in the US. This fact has been called 'the epidemiological paradox of low birthweight'. Natality data from Brazil revealed the existence of a similar paradox: LBW rates are higher in more developed than in less developed regions within the country. In this study, data from two population-based cohort studies carried out in the nineties, including 2439 births in Sao Luis, a poor city in north-eastern Brazil, and 2839 births in Ribeirao Preto, a socio-economically well-off city in south-eastern Brazil, were used to explore this paradox. The method proposed by Wilcox and Russell and a graphic analysis of the frequency distribution of birthweight according to gestational age were used to provide indirect information about possible gestational age misclassification. Contrary to expectations, the LBW rate was higher in Ribeirao Preto than in Sao Luis (10.7 vs. 7.6%, P <0.001), while preterm birth (PTB) rate (12.7 vs. 12.1%, P=0.520) and percentage of small-for-gestational-age (SGA) infants (12.5 vs. 13.5%, P=0.290) were similar for the two cities. However, SGA rate among preterm infants was higher in Ribeirao Preto (16.4 vs. 9.8%, P=0.014). A bimodal distribution of birthweight was observed for children with less than 32 weeks in Sao Luis. As estimated by the Wilcox and Russell method, the residual distribution was greater in Ribeirao Preto than in Sao Luis (3.4 vs. 2.4%). Part of the LBW paradox observed for the two cities was due to the higher PTB rate and higher number of preterm SGA infants in Ribeirao Preto. Factors such as greater medical intervention in preterm newborns close to the end of pregnancy in more developed municipalities, artefacts in the determination of gestational age, and the under-registration of livebirths and registration of livebirths as stillbirths in less developed municipalities may explain why LBW rates in Brazil are higher in richer than in poorer municipalities.
Asunto(s)
Recién Nacido de Bajo Peso , Peso al Nacer/fisiología , Brasil/epidemiología , Distribución de Chi-Cuadrado , Estudios de Cohortes , Edad Gestacional , Humanos , Recién Nacido de Bajo Peso/fisiología , Recién Nacido , Nacimiento Prematuro/epidemiología , Prevalencia , Factores Socioeconómicos , Salud UrbanaRESUMEN
OBJECTIVE: To obtain population estimates and profile risk factors for infant mortality in two birth cohorts and compare them among cities of different regions in Brazil. METHODS: In Ribeirão Preto, southeast Brazil, infant mortality was determined in a third of hospital live births (2,846 singleton deliveries) in 1994. In São Luís, northeast Brazil, data were obtained using systematic sampling of births stratified by maternity unit (2,443 singleton deliveries) in 1997-1998. Mothers answered standardized questionnaires shortly after delivery and information on infant deaths was retrieved from hospitals, registries and the States Health Secretarys' Office. The relative risk (RR) was estimated by Poisson regression. RESULTS: In São Luís, the infant mortality rate was 26.6/1,000 live births, the neonatal mortality rate was 18.4/1,000 and the post-neonatal mortality rate was 8.2/1,000, all higher than those observed in Ribeirão Preto (16.9, 10.9 and 6.0 per 1,000, respectively). Adjusted analysis revealed that previous stillbirths (RR=3.67 vs 4.13) and maternal age <18 years (RR=2.62 vs 2.59) were risk factors for infant mortality in the two cities. Inadequate prenatal care (RR=2.00) and male sex (RR=1.79) were risk factors in São Luís only, and a dwelling with 5 or more residents was a protective factor (RR=0.53). In Ribeirão Preto, maternal smoking was associated with infant mortality (RR=2.64). CONCLUSIONS: In addition to socioeconomic inequalities, differences in access to and quality of medical care between cities had an impact on infant mortality rates.
Asunto(s)
Mortalidad Infantil , Dinámica Poblacional , Adolescente , Adulto , Brasil/epidemiología , Estudios de Cohortes , Femenino , Edad Gestacional , Humanos , Lactante , Masculino , Edad Materna , Embarazo , Factores de Riesgo , Factores SocioeconómicosRESUMEN
OBJETIVO: Obter estimativas populacionais e fatores de risco de mortalidade infantil em coortes de nascimentos e comparar esses fatores entre cidades de diferentes regiões do País. MÉTODOS: Em Ribeirão Preto, SP, a mortalidade infantil foi avaliada em 1/3 dos nascidos vivos hospitalares (2.846 partos únicos) em 1994. Em São Luís, MA, foi feita amostragem sistemática de partos estratificada por maternidade (2.443 partos únicos) em 1997/98. As mães responderam a questionários padronizados logo após o parto e as informações sobre os óbitos foram coletadas nos hospitais, nos cartórios e nas secretarias estaduais de saúde. Risco relativo (RR) e intervalo de confiança de 95 por cento foram estimados pela regressão de Poisson. RESULTADOS: O coeficiente de mortalidade infantil (CMI) em São Luís foi 26,6/1.000 nascidos vivos, o coeficiente de mortalidade neonata (CMN)l 18,4/1.000 e o coeficiente de mortalidade pós-neonatal (CMPN) 8,2/1.000, valores superiores aos de Ribeirão Preto, com CMI 16,9/1.000, CMN 10,9/1.000,CMPN 6,0/1.000. Na análise ajustada, nas duas cidades, natimorto prévio (RR=3,67 vs 4,13) e idade materna <18 anos (RR=2,62 vs 2,59) foram fatores de risco para a mortalidade infantil. Apenas em São Luís, o pré-natal inadequado (RR=2,00) e o sexo masculino (RR=1,79) foram fatores de risco, e domicílios com 5 ou mais moradores foram fatores protetores (RR=0,53). Em Ribeirão Preto, o hábito materno de fumar foi associado à mortalidade infantil (RR=2,64). CONCLUSÕES: Além de desigualdades socioeconômicas, diferenças no acesso e na qualidade da atenção médica entre as cidades influenciaram as taxas de mortalidade infantil.
Asunto(s)
Mortalidad Infantil , Mortalidad , Mortalidad Infantil , Factores Socioeconómicos , Factores de Riesgo , Mortalidad Infantil , Recién Nacido de Bajo PesoRESUMEN
OBJECTIVE: To identify factors associated with inadequacy of prenatal care utilization in urban community. METHODS: A cross-sectional study of a systematic sample stratified by maternity hospital, consisting of hospital births in the municipality of São Luís, Brazil, was carried out from March 1997 to February 1998. Socioeconomic and demographic factors, reproductive health, morbidity during pregnancy, and utilization of prenatal care services were studied. Mothers answered a standardized questionnaire before hospital discharge. The adequacy of prenatal care utilization was analyzed by means of two indexes: APNCU (Adequacy of Prenatal Care Utilization) and a new index based on the recommendations of the Brazilian Ministry of Health. RESULTS: There were interviewed 2,831 women who delivered at 10 public and private maternity hospitals. The inadequacy of prenatal care utilization was 49.2% according to the APNCU index and 24.5% when determined by the Brazilian index. Prenatal care at public services, low maternal schooling, low income, having no partner, and absence of maternal diseases during pregnancy were associated with inadequacy of prenatal care use according to both indexes. High parity and maternal age of 35 years or more were also associated with inadequacy, whereas primiparity, morbidity, and young maternal age (<20 years) seemed to protect from inadequacy when the Brazilian index was used. CONCLUSIONS: Prenatal care showed low coverage in the municipality of São Luís. The inadequacy of prenatal care utilization was associated with several factors linked to social inequality.
Asunto(s)
Atención Prenatal/estadística & datos numéricos , Adolescente , Adulto , Factores de Edad , Brasil , Estudios Transversales , Femenino , Humanos , Embarazo , Factores de Riesgo , Justicia Social , Factores SocioeconómicosRESUMEN
OBJETIVO: Identificar fatores associados à inadequaçäo do uso da assistência pré-natal em comunidade urbana. MÉTODOS: Foi realizado estudo transversal em amostra sistemática, estratificada por maternidades, de todos os nascimentos hospitalares do município de Säo Luís, MA, no período de março de 1997 a fevereiro de 1998. Foram avaliados indicadores socioeconômicos e demográficos, de saúde reprodutiva, morbidade na gravidez e utilizaçäo de serviços pré-natais. Utilizou-se questionário padronizado respondido pelas puérperas antes da alta hospitalar. A adequaçäo do uso da assistência pré-natal foi analisada pelo índice "Adequacy of Prenatal Care Utilization" (APNCU) e por um novo índice proposto, baseado nas recomendaçöes do Ministério da Saúde, Brasil. RESULTADOS: Foram entrevistadas 2.831 puérperas, atendidas em dez unidades de saúde pública e privada. A inadequaçäo do uso da assistência pré-natal foi de 49,2por cento pelo índice APNCU, e de 24,5por cento pelo novo índice proposto. Mulheres atendidas em serviços públicos de saúde, de baixa escolaridade e baixa renda familiar, sem companheiro ou com doença durante a gravidez, tiveram maiores percentuais de inadequaçäo do uso do atendimento pré-natal, pelos dois índices analisados. Pelo novo índice proposto, maiores percentuais de inadequaçäo foram associados à alta paridade e idade materna, enquanto baixa idade materna (<20 anos), ocorrência de doença durante a gravidez e primiparidade sugerem proteçäo contra a inadequaçäo. CONCLUSOES: O atendimento pré-natal em Säo Luís do Maranhäo apresentou baixa cobertura. A inadequaçäo do uso da assistência esteve associada a vários fatores indicativos da persistência de desigualdade social