title: Sexual behavior among Brazilian adolescents, National Adolescent School-based Health Survey (PeNSE 2012).
abstract: OBJECTIVE
  This study describes the sexual behavior among students who participated in the National Adolescent School-based Health Survey (PeNSE) 2012 and investigates whether social inequalities, the use of psychoactive substances and the dissemination of information on sexual and reproductive health in school are associated with differences in behavior.
  
  
  METHODS
  The response variable was the sexual behavior described in three categories (never had sexual intercourse, had protected sexual intercourse, had unprotected sexual intercourse). The explanatory variables were grouped into socio- demographic characteristics, substance use and information on sexual and reproductive health in school. Variables associated with the conduct and unprotected sex were identified through multinomial logistic regression, using "never had sexual intercourse" as a reference.
  
  
  RESULTS
  Over nearly a quarter of the adolescents have had sexual intercourse in life, being more frequent among boys. About 25% did not use a condom in the last intercourse. Low maternal education and work increased the chance of risky sexual behavior. Any chance of protected and unprotected sex increased with the number of psychoactive substances used. Among those who don't receive guidance on the prevention of pregnancy in school, the chance to have sexual intercourse increased, with the largest magnitude for unprotected sex (OR = 1.41 and OR = 1.87 ).
  
  
  CONCLUSIONS
  The information on preventing pregnancy and STD/AIDS need to be disseminated before the 9th grade. Social inequalities negatively affect risky sexual behavior. Substance use is strongly associated with unprotected sex. Information on the prevention of pregnancy and STD/AIDS need to be disseminated early.
authors: Departament of Disease and Non-Communicable Condition Surveillance and Health Promotion, Ministry of Health, Brasília, DF, Brazil.
authors: Maryane
authors: M
authors: Oliveira-Campos
authors: Departament of Disease and Non-Communicable Condition Surveillance and Health Promotion, Ministry of Health, Brasília, DF, Brazil.
authors: Marília Lavocart
authors: ML
authors: Nunes
authors: Brazilian Institute of Geography and Statistics, Rio de Janeiro, RJ, Brazil.
authors: Fátima de Carvalho
authors: Fde C
authors: Madeira
authors: Brazilian Institute of Geography and Statistics, Rio de Janeiro, RJ, Brazil.
authors: Maria Goreth
authors: MG
authors: Santos
authors: Brazilian Institute of Geography and Statistics, Rio de Janeiro, RJ, Brazil.
authors: Silvia Reise
authors: SR
authors: Bregmann
authors: Departament of Disease and Non-Communicable Condition Surveillance and Health Promotion, Ministry of Health, Brasília, DF, Brazil.
authors: Deborah Carvalho
authors: DC
authors: Malta
authors: Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.
authors: Luana
authors: L
authors: Giatti
authors: Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.
authors: Sandhi Maria
authors: SM
authors: Barreto
mesh_terms: D000293:Adolescent; D000294:Adolescent Behavior; D001938:Brazil; D002648:Child; D005260:Female; D006306:Health Surveys; D006801:Humans; D008297:Male; D015999:Multivariate Analysis; D012309:Risk-Taking; D012574:Schools; D012725:Sexual Behavior / Q000706:statistics & numerical data*; D012959:Socioeconomic Factors; D019966:Substance-Related Disorders / Q000453:epidemiology