title: The epidemiologic paradox of low birth weight in Brazil.
abstract: OBJECTIVE
  To examine whether the low birth weight (LBW) paradox exists in Brazil.
  
  
  METHODS
  LBW and cesarean section rates between 1995 and 2007 were estimated based on data from SINASC (Brazilian Live Births Database). Infant mortality rates (IMRs) were obtained using an indirect method that correct for underreporting. Schooling information was obtained from census data. Trends in LBW rate were assessed using joinpoint regression models. The correlations between LBW rate and other indicators were graphically assessed by lowess regression and tested using Spearman's rank correlation.
  
  
  RESULTS
  In Brazil, LBW rate trends were non-linear and non-significant: the rate dropped from 7.9% in 1995 to 7.7% in 2000, then increased to 8.2% in 2003 and remained nearly steady thereafter at 8.2% in 2007. However, trends varied among Brazilian regions: there were significant increases in the North from 1999 to 2003 (2.7% per year), and in the South (1.0% per year) and Central-West regions (0.6% per year) from 1995 to 2007. For the entire period studied, higher LBW and lower IMRs were seen in more developed compared to less developed regions. In Brazilian States, in 2005, the higher the IMR rate, the lower the LBW rate (p=0.009); the lower the low schooling rate, the lower the LBW rate (p=0.007); the higher the number of neonatal intensive care beds per 1,000 live births, the higher the LBW rate (p=0.036).
  
  
  CONCLUSIONS
  The low birth weight paradox was seen in Brazil. LBW rate is increasing in some Brazilian regions. Regional differences in LBW rate seem to be more associated to availability of perinatal care services than underlying social conditions.
authors.affiliation: Departamento de Saúde Pública, Universidade Federal do Maranhão, São Luís, MA, Brasil. aasilva@elo.com.br
authors.forename: Antônio Augusto Moura da
authors.initials: AA
authors.lastname: Silva
authors.forename: Leopoldo Muniz da
authors.initials: LM
authors.lastname: Silva
authors.forename: Marco Antonio
authors.initials: MA
authors.lastname: Barbieri
authors.forename: Heloísa
authors.initials: H
authors.lastname: Bettiol
authors.forename: Luciana Mendes de
authors.initials: LM
authors.lastname: Carvalho
authors.forename: Valdinar Sousa
authors.initials: VS
authors.lastname: Ribeiro
authors.forename: Marcelo Zubaran
authors.initials: MZ
authors.lastname: Goldani
mesh_terms: D001938:Brazil / Q000453:epidemiology; D002585:Cesarean Section / Q000706:statistics & numerical data; D004522:Educational Status; D005260:Female; D006801:Humans; D007226:Infant Mortality / Q000639:trends*; D007230:Infant, Low Birth Weight; D007231:Infant, Newborn; D011247:Pregnancy; D015995:Prevalence