title: Infant mortality: comparison between two birth cohorts from Southeast and Northeast, Brazil.
abstract: 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.
authors.affiliation: Departamento de Pediatria, Universidade Federal do Maranhão, São Luís, MA, Brazil. zmribeiro@uol.com.br
authors.forename: Valdinar S
authors.initials: VS
authors.lastname: Ribeiro
authors.forename: Antônio A M
authors.initials: AA
authors.lastname: Silva
authors.forename: Marco A
authors.initials: MA
authors.lastname: Barbieri
authors.forename: Heloisa
authors.initials: H
authors.lastname: Bettiol
authors.forename: Vânia M F
authors.initials: VM
authors.lastname: Aragão
authors.forename: Liberata C
authors.initials: LC
authors.lastname: Coimbra
authors.forename: Maria T S S B
authors.initials: MT
authors.lastname: Alves
mesh_terms: D000293:Adolescent; D000328:Adult; D001938:Brazil / Q000453:epidemiology; D015331:Cohort Studies; D005260:Female; D005865:Gestational Age; D006801:Humans; D007223:Infant; D007226:Infant Mortality; D008297:Male; D008423:Maternal Age; D011157:Population Dynamics; D011247:Pregnancy; D012307:Risk Factors; D012959:Socioeconomic Factors