title: Type of contraception method used at last intercourse and associations with health risk behaviors among US adolescents.
abstract: BACKGROUND
  This study was conducted to examine associations with contraception methods used at last sexual intercourse among US adolescents.
  
  
  METHODS
  Data consisted of sexually active adolescents (9th-12th grade, weighted n=24,638) from the 1999-2007 Youth Risk Behavior Surveillance System (YRBSS). We performed multinomial multivariable logistic regression analyses with condom users at last sexual intercourse as the reference group.
  
  
  RESULTS
  Males who used alcohol, cigarettes, marijuana and cocaine were more likely to use no method/unsure of method (OR=2.4, CI=1.7-3.4) or rely on withdrawal (OR=2.6, CI=1.5-4.3). Females with six or more sexual partners were more likely to rely on withdrawal (OR=2.9, CI=2.1-3.9) or contraception methods that offer no STI protection [i.e., birth control pills: OR=1.9, CI=1.4-2.5; and depot medroxyprogesterone acetate (DMPA, marketed as Depo-Provera): OR=2.6, CI=1.6-4.2]. Earlier age of sexual debut was also associated with nonuse.
  
  
  CONCLUSIONS
  Prevention efforts should focus on at-risk adolescents including substance-using males, females with six or more sexual partners, and those who initiate sexual intercourse at an early age.
authors.affiliation: Department of Psychiatry, Washington University School of Medicine, Campus Box 8134, St. Louis, MO 63110, USA. rehgp@psychiatry.wustl.edu
authors.forename: Patricia A
authors.initials: PA
authors.lastname: Cavazos-Rehg
authors.forename: Melissa J
authors.initials: MJ
authors.lastname: Krauss
authors.forename: Edward L
authors.initials: EL
authors.lastname: Spitznagel
authors.forename: Mario
authors.initials: M
authors.lastname: Schootman
authors.forename: Jeffrey F
authors.initials: JF
authors.lastname: Peipert
authors.forename: Linda B
authors.initials: LB
authors.lastname: Cottler
authors.forename: Laura Jean
authors.initials: LJ
authors.lastname: Bierut
mesh_terms: D000293:Adolescent; D000294:Adolescent Behavior; D000428:Alcohol Drinking / Q000453:epidemiology; D002188:Cannabis; D003042:Cocaine; D003075:Coitus; D017280:Condoms; D003267:Contraception / Q000379:methods*; D003271:Contraceptive Agents, Female / Q000008:administration & dosage; D005260:Female; D006801:Humans; D008297:Male; D017258:Medroxyprogesterone Acetate / Q000008:administration & dosage; D012309:Risk-Taking; D012725:Sexual Behavior / Q000706:statistics & numerical data; D012747:Sexual Partners; D012907:Smoking / Q000453:epidemiology; D019966:Substance-Related Disorders / Q000453:epidemiology*; D014481:United States / Q000453:epidemiology
chemical_list: D003271:Contraceptive Agents, Female; D017258:Medroxyprogesterone Acetate; D003042:Cocaine