title: Adolescent pregnancy prevention: An abstinence-centered randomized controlled intervention in a Chilean public high school.
abstract: OBJECTIVE
  To evaluate the efficacy of an abstinence-centered sex education program in adolescent pregnancy prevention, the TeenSTAR Program was applied in a high school in Santiago, Chile.
  
  
  METHODS
  A total of 1259 girls from a Santiago high school were divided into three cohorts depending on the year they started high school: the 1996 cohort of 425 students, which received no intervention; the 1997 cohort, in which 210 students received an intervention and 213 (control group) did not; and the 1998 cohort, in which 328 students received an intervention and 83 (control group) did not. Students were randomly assigned to control and intervention groups in these cohorts, before starting with the program. We conducted a prospective, randomized study using the application of the TeenSTAR sex education program during the first year of high school to the intervention groups in the 1997 and 1998 cohorts. All cohorts were followed up for 4 years; pregnancy rates were recorded and subsequently contrasted in the intervention and control groups. Pregnancy rates were measured and Risk Ratio with 95% confidence interval were calculated for intervention and control groups in each cohort.
  
  
  RESULTS
  Pregnancy rates for the intervention and control groups in the 1997 cohort were 3.3% and 18.9%, respectively (RR: 0.176, CI: 0.076-0.408). Pregnancy rates for the intervention and control groups in the 1998 cohort were 4.4% and 22.6%, respectively (RR 0.195, CI: 0.099-0.384).
  
  
  CONCLUSIONS
  The abstinence-centered TeenSTAR sex education intervention was effective in the prevention of unintended adolescent pregnancy.
authors.affiliation: Department of Obstetrics and Gynecology, Faculty of Medicine, Universidad de los Andes, Santiago, Chile. ccabezon@uandes.cl
authors.forename: Carlos
authors.initials: C
authors.lastname: Cabezón
authors.forename: Pilar
authors.initials: P
authors.lastname: Vigil
authors.forename: Iván
authors.initials: I
authors.lastname: Rojas
authors.forename: M Eugenia
authors.initials: ME
authors.lastname: Leiva
authors.forename: Rosa
authors.initials: R
authors.lastname: Riquelme
authors.forename: Waldo
authors.initials: W
authors.lastname: Aranda
authors.forename: Carlos
authors.initials: C
authors.lastname: García
mesh_terms: D000293:Adolescent; D000294:Adolescent Behavior; D002677:Chile; D005260:Female; D006801:Humans; D011247:Pregnancy; D011253:Pregnancy in Adolescence / Q000517:prevention & control*; D012572:School Health Services; D012746:Sexual Abstinence; D016896:Treatment Outcome