title: Characteristics associated with sex after periods of abstinence among sexually experienced young women.
abstract: BACKGROUND
  Adolescent pregnancy prevention is difficult because adolescent sex is intermittent. Understanding why sexually experienced adolescents have sex after a period of abstinence will help clinicians to tailor counseling.
  
  
  METHODS
  For up to 4.5 years between 1999 and 2006, a sample of 354 adolescent women recruited at urban primary care clinics were interviewed and tested for STDs every three months, and were asked to complete three months of daily diaries twice a year. Survival analyses were used to estimate associations between intrapersonal, relationship and STD-related characteristics and the risk of ending an abstinence period with sex.
  
  
  RESULTS
  Participants reported 9,236 abstinence periods, which averaged 31 days. The risk that an abstinence period ended with sex increased steeply for periods of fewer than 17 days (short), rose less steeply for 17-39-day (intermediate) periods and was fairly steady for longer periods. For short periods, the risk increased with age, sexual interest, positive mood, partner support, relationship quality and history of STD diagnosis more than three months ago (hazard ratios, 1.02-1.2); it decreased as negative mood increased (0.98) and was reduced among adolescents with a recent STD diagnosis (0.9). For intermediate periods, the association with a recent STD diagnosis became positive (1.4). For long periods, sex was associated only with age, sexual interest and relationship quality.
  
  
  CONCLUSIONS
  To provide targeted and timely sexual health counseling, clinicians may want to ask adolescents not only whether they are sexually active but also when they last had sex.
authors.affiliation: Section of Adolescent Medicine, Department of Pediatrics, Indiana University School of Medicine, Indianapolis, USA. maott@iupui.edu
authors.forename: Mary A
authors.initials: MA
authors.lastname: Ott
authors.forename: Susan
authors.initials: S
authors.lastname: Ofner
authors.forename: Wanzhu
authors.initials: W
authors.lastname: Tu
authors.forename: Barry P
authors.initials: BP
authors.lastname: Katz
authors.forename: J Dennis
authors.initials: JD
authors.lastname: Fortenberry
mesh_terms: D000293:Adolescent; D005260:Female; D006801:Humans; D007196:Indiana; D007407:Interviews as Topic; D011247:Pregnancy; D011253:Pregnancy in Adolescence / Q000517:prevention & control; D012746:Sexual Abstinence; D012725:Sexual Behavior; D012749:Sexually Transmitted Diseases; D011795:Surveys and Questionnaires