title: Factors associated with low birth weight in a historical series of deliveries in Campinas, Brazil.
abstract: OBJECTIVE
  To identify the risk factors associated with low birth weight (< 2500 grams).
  
  
  METHODS
  Unmatched case-control study performed in a tertiary maternity hospital in Campinas, Brazil, involving 43,499 liveborn infants delivered in the institution between 1986 and 2004. Analysis of the database containing information on deliveries of women who gave birth to infants with low (6,477 cases) and normal (37,467) birth weight were performed. Factors associated with low birth weight were identified according to the odds ratio (OR) and 95% confidence interval (95%CI) in the bivariate analysis and according to the adjusted OR in the multivariate analysis. Sociodemographic characteristics, reproductive history, previous morbidity and factors related to current prenatal care were studied.
  
  
  RESULTS
  Extremes of reproductive age, poor education, low maternal weight, smoking beyond the fourth month of pregnancy, previous cesarean section, interdelivery interval < or = 24 months and > or 37 months, maternal history of hypertension, cardiopathy and premature delivery, few (< or = 5) prenatal visits and beginning prenatal care late in pregnancy (after the 3rd month), premature rupture of membranes, increased blood pressure, infectious diseases and hemorrhages during current pregnancy were all associated with low birth weight. Maternal obesity and being a primipara were found to be protective factors.
  
  
  CONCLUSIONS
  These results confirm the findings of previous studies. The detection and prenatal management of modifiable factors, counseling, pre-conception intervention, adequate prenatal care and the implementation of primary and secondary prevention of maternal morbidity should be a target for all obstetrician as a potential source for reducing the incidence of low birth weight.
authors.affiliation: Universidade Estadual de Campinas, Campinas, SP.
authors.forename: Pedro Ribeiro
authors.initials: PR
authors.lastname: Coutinho
authors.forename: José Guilherme
authors.initials: JG
authors.lastname: Cecatti
authors.forename: Fernanda Garanhani
authors.initials: FG
authors.lastname: Surita
authors.forename: João Paulo de
authors.initials: JP
authors.lastname: Souza
authors.forename: Sirlei Siani de
authors.initials: SS
authors.lastname: Morais
mesh_terms: D000293:Adolescent; D000328:Adult; D001938:Brazil; D016022:Case-Control Studies; D002648:Child; D005260:Female; D006801:Humans; D007230:Infant, Low Birth Weight; D007231:Infant, Newborn; D008423:Maternal Age; D015999:Multivariate Analysis; D011247:Pregnancy; D047928:Premature Birth / Q000209:etiology*; D011295:Prenatal Care; D012307:Risk Factors; D012959:Socioeconomic Factors; D055815:Young Adult