title: Childbearing in adolescence: intergenerational dejà-vu? Evidence from a Brazilian birth cohort.
abstract: BACKGROUND
  Pregnancy in adolescence tends to repeat over generations. This event has been little studied in middle and low-income societies undergoing a rapid epidemiological transition. To assess this association it is important to adjust for socioeconomic conditions at different points in lifetime. Therefore, the aim of this study is to analyze the independent effect of adolescent childbearing in a generation on its recurrence in the subsequent generation, after adjusting for socioeconomic status at different points in life.
  
  
  METHODS
  The study was conducted on a prospective cohort of singleton liveborn females from the city of Ribeirão Preto, Brazil, evaluated in 1978/79, and their daughters assessed in 2002/04. A total of 1059 mother-daughter pairs were evaluated. The women who had their first childbirth before 20 years of age were considered to be adolescent mothers. The risk of childbearing in adolescence for the daughter was modeled as a function of the occurrence of teenage childbearing in her mother, after adjustment for socio-demographic variables in a Poisson regression model.
  
  
  RESULTS
  The rate of childbearing during adolescence was 31.4% in 1978/79 and 17.1% in 2002/04. Among the daughters of the 1st generation adolescent mothers, this rate was 26.7%, as opposed to 12.7% among the daughters of non adolescent mothers. After adjustments the risk of adolescent childbearing for the 2nd generation was 35% higher for women whose mothers had been pregnant during adolescence - RR = 1.35 (95% CI 1.04-1.74).
  
  
  CONCLUSIONS
  Adolescent childbearing in the 1st generation was a predictor of adolescent childbearing in the 2nd, regardless of socioeconomic factors determined at different points in lifetime.
authors.affiliation: Faculty of Medicine, University of São Paulo, Avenida Dr, Enéas Carvalho de Aguiar 647, São Paulo, Brazil. ferraro@usp.br
authors.forename: Alexandre Archanjo
authors.initials: AA
authors.lastname: Ferraro
authors.forename: Viviane Cunha
authors.initials: VC
authors.lastname: Cardoso
authors.forename: Aline Pires
authors.initials: AP
authors.lastname: Barbosa
authors.forename: Antônio Augusto Moura
authors.initials: AA
authors.lastname: Da Silva
authors.forename: Carlos Augusto
authors.initials: CA
authors.lastname: Faria
authors.forename: Valdinar Souza
authors.initials: VS
authors.lastname: De Ribeiro
authors.forename: Heloisa
authors.initials: H
authors.lastname: Bettiol
authors.forename: Marco Antonio
authors.initials: MA
authors.lastname: Barbieri
mesh_terms: D000293:Adolescent; D001938:Brazil; D005191:Family Characteristics; D005260:Female; D006801:Humans; D016901:Intergenerational Relations; D009035:Mothers; D009679:Nuclear Family; D016012:Poisson Distribution; D011247:Pregnancy; D011253:Pregnancy in Adolescence; D011446:Prospective Studies; D012008:Recurrence; D012307:Risk Factors; D012959:Socioeconomic Factors