title: Tobacco and alcohol use in adolescents with unplanned pregnancies: relation with family structure, tobacco and alcohol use at home and by friends.
abstract: BACKGROUND
  Recent publications show that smoking and alcohol use among adolescents with unplanned pregnancy is increasing and the causes need to be further studied.
  
  
  OBJECTIVE
  To determine the association between living in a non-intact family household and the presence of smokers and consumers of alcoholic beverages in the adolescents' environment with smoking and consuming alcoholic beverages in adolescents with unplanned pregnancies.
  
  
  METHODS
  A cross-sectional study was carried out among 785 pregnant adolescents, aged 13-19 years. Data was collected by trained interviewers using a self-administered questionnaire. The association was determined using multivariate logistic regression analysis.
  
  
  RESULTS
  In adolescents with unplanned pregnancies, the prevalence of active smoking was 21.2% and of alcohol consumption, 41.5%. The percentage of smoking at home was 57.4% and alcohol consumption, 77.5%. Approximately, 80.3% of adolescents with unplanned pregnancies had friends who smoked and 90.6% consumed alcoholic beverages. Multivariate logistic regression analysis shows that having friends who smoke or who consume alcoholic beverages is the most important risk factor for substance use in adolescents with unplanned pregnancies. Smoking and alcohol consumption at home are not associated with smoking in adolescents with unplanned pregnancies.
  
  
  CONCLUSIONS
  Socializing with friends who smoke and/or consume alcoholic beverages constitutes the most important risk factor for substance use among adolescents with unplanned pregnancies.
authors.affiliation: Autonomus University of Tamaulipas, Faculty of Medicine of Tamaulipas.
authors.forename: Vazquez-Nava
authors.initials: VN
authors.lastname: Francisco
authors.affiliation: Social Security Mexican Institute, Shout of Veracruz Delegation.
authors.forename: Vazquez-Rodríguez
authors.initials: VR
authors.lastname: Carlos
authors.affiliation: Veracruzana University, Faculty of Medicine, Mexico.
authors.forename: Vazquez-Rodriguez
authors.initials: VR
authors.lastname: Eliza
authors.affiliation: Autonomus University of Tamaulipas, Unidad Académica Multidisciplinaria Reynosa Aztlán, Mexico.
authors.forename: Castillo-Ruiz
authors.initials: CR
authors.lastname: Octelina
authors.affiliation: University of Granada, Faculty of Medicine.
authors.forename: Iribar Ibabe
authors.initials: II
authors.lastname: Maria
mesh_terms: D000293:Adolescent; D000294:Adolescent Behavior / Q000523:psychology*; D000428:Alcohol Drinking / Q000453:epidemiology*; D003430:Cross-Sectional Studies; D005191:Family Characteristics; D005260:Female; D006801:Humans; D011247:Pregnancy; D011253:Pregnancy in Adolescence / Q000523:psychology*; D049168:Pregnancy, Unplanned; D015995:Prevalence; D012307:Risk Factors; D012725:Sexual Behavior / Q000706:statistics & numerical data*; D012907:Smoking / Q000453:epidemiology*; D012931:Social Environment; D019966:Substance-Related Disorders / Q000453:epidemiology; D011795:Surveys and Questionnaires; D014026:Nicotiana
keywords: Family; adolescents; substance use; unplanned pregnancy