title: Sexual activity and contraceptive use amongst teenagers under the age of 15 years.
abstract: OBJECTIVE
  The aims of this study were to document patterns of sexual activity and contraceptive use in a sample of 952 Christchurch born children studied to the age of 15 years.
  
  
  METHODS
  Data on sexual activity and contraceptive use was collected on the basis of self report at ages 14 and 15 years.
  
  
  RESULTS
  By the age of 15 years, 8.5% of this sample had engaged in sexual intercourse. Early sexual activity was more common amongst girls, amongst children of Maori or Pacific Island ethnicity and among children from families of unskilled or semi-skilled socioeconomic status. Of those who were sexually active just under half (49.4%) reported having intercourse with only one partner while 17.3% (1.5% of the total sample) reported sexual experience with more than three partners by the age of 15 years. There was a high rate of contraceptive usage in the sample with 88.9% of those who were sexually active having used a recognised form of contraception and it was estimated that approximately 87% of sexual acts reported by this sample involved the use of contraception. The high rate of contraceptive usage for the sample was accounted for largely by the use of the condom and over 80% of those who were sexually active reported using this method. Despite the high rate of contraceptive usage evident for the sample just under one third of those who were sexually active reported having unprotected intercourse on at least one occasion.
  
  
  CONCLUSIONS
  Bearing in mind the possibility of under reporting of sexual activity, the results suggest that by the age of 15 years in the region of 1 in 10 teenagers were sexually active. The major finding to emerge from the study was a high rate of utilisation of contraceptive methods, particularly the condom. It seems likely that this high rate of condom usage is a reflection of the effects of publicity and public education campaigns about the risks of HIV infection, AIDS and the need for safe sex. Despite the high rate of contraceptive usage for this sample it is suggested that those engaging in early sexual behaviour are a high risk population in need of support, assistance and counselling.
authors.affiliation: Christchurch Health and Development Study, Christchurch School of Medicine, Christchurch Hospital.
authors.forename: M T
authors.initials: MT
authors.lastname: Lynskey
authors.forename: D M
authors.initials: DM
authors.lastname: Fergusson
mesh_terms: D000293:Adolescent; D000294:Adolescent Behavior; D000367:Age Factors; D015331:Cohort Studies; D003268:Contraception Behavior / Q000208:ethnology / Q000706:statistics & numerical data; D005006:Ethnicity; D005260:Female; D006801:Humans; D016015:Logistic Models; D008137:Longitudinal Studies; D008297:Male; D009520:New Zealand; D015995:Prevalence; D012650:Self Disclosure; D012725:Sexual Behavior / Q000208:ethnology / Q000706:statistics & numerical data*; D012747:Sexual Partners; D012959:Socioeconomic Factors