title: The changing pattern of contraceptive use and pregnancies in four generations of young women.
abstract: BACKGROUND
  The aim of this study was to describe contraceptive use and pregnancies and their relationship to socio-economic status (SES) in four generations of young Swedish women.
  
  
  METHODS
  Questionnaires regarding contraceptive use and pregnancies were sent to random samples of 19-year-old women in 1981, 1991, 2001 and 2011 (n = 4732).
  
  
  RESULTS
  Current contraceptive use was higher in 2001 (78%) (p < 0.01) and 2011 (69%) (p < 0.05) compared with 1981 (60%) and 1991 (62%). Combined hormonal contraception (CHC) was the most common form of contraception throughout (p < 0.0001). The use of long-acting reversible contraception (LARC = implants, intrauterine contraception) and progestogen-only pills increased over time (p < 0.01). Mental side effects as a reason for CHC cessation increased over time and was the most common reason for cessation of CHC in 2011 (p < 0.001). Contraceptive use was lower in women from low SES areas (p < 0.05) in 2011. The percentage of young women who had been pregnant at ≤19 years of age was lower (p < 0.05) in the assessment from 2001 (7%) than in that in 1991 (13%) and 2011 (12%). The proportion of teenage mothers decreased from 4.4% (1981) to 1.6% (2011) (p < 0.01). More women had been pregnant at ≤19 years of age in low SES areas than in middle and high SES areas (p < 0.05).
  
  
  CONCLUSIONS
  The lowest pregnancy rate was in the cohort with the highest contraceptive use. Term pregnancies declined over time. A greater number of pregnancies in low SES areas and a change towards lower contraceptive use in low SES areas was recorded in 2011.
authors.affiliation: Department of Obstetrics and Gynecology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden. ingela.lindh@vgregion.se.
authors.forename: Ingela
authors.initials: I
authors.lastname: Lindh
authors.affiliation: Department of Obstetrics and Gynecology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden.
authors.forename: Helena
authors.identifier: http://orcid.org/0000-0003-2405-0662
authors.initials: H
authors.lastname: Hognert
authors.affiliation: Department of Obstetrics and Gynecology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden.
authors.forename: Ian
authors.identifier: http://orcid.org/0000-0002-0400-5509
authors.initials: I
authors.lastname: Milsom
mesh_terms: D003267:Contraception / Q000379:methods / Q000706:statistics & numerical data* / Q000639:trends*; D003268:Contraception Behavior / Q000706:statistics & numerical data / Q000639:trends*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D011247:Pregnancy; D018873:Pregnancy Rate / Q000639:trends*; D011446:Prospective Studies; D012923:Social Class; D013548:Sweden; D055815:Young Adult
keywords: Contraception; body mass index; cross-sectional study; epidemiology; smoking; socio-economic status; teenage pregnancy