title: Sexual behaviour in Britain: partnerships, practices, and HIV risk behaviours.
abstract: BACKGROUND
  Sexual behaviour is a major determinant of sexual and reproductive health. We did a National Survey of Sexual Attitudes and Lifestyles (Natsal 2000) in 1999-2001 to provide population estimates of behaviour patterns and to compare them with estimates from 1990-91 (Natsal 1990).
  
  
  METHODS
  We did a probability sample survey of men and women aged 16-44 years who were resident in Britain, using computer-assisted interviews. Results were compared with data from respondents in Natsal 1990.
  
  
  RESULTS
  We interviewed 11161 respondents (4762 men, 6399 women). Patterns of heterosexual and homosexual partnership varied substantially by age, residence in Greater London, and marital status. In the past 5 years, mean numbers of heterosexual partners were 3.8 (SD 8.2) for men, and 2.4 (SD 4.6) for women; 2.6% (95% CI 2.2-3.1) of both men and women reported homosexual partnerships; and 4.3% (95% CI 3.7-5.0) of men reported paying for sex. In the past year, mean number of new partners varied from 2.04 (SD 8.4) for single men aged 25-34 years to 0.05 (SD 0.3) for married women aged 35-44 years. Prevalence of many reported behaviours had risen compared with data from Natsal 1990. Benefits of greater condom use were offset by increases in reported partners. Changes between surveys were generally greater for women than men and for respondents outside London.
  
  
  CONCLUSIONS
  Our study provides updated estimates of sexual behaviour patterns. The increased reporting of risky sexual behaviours is consistent with changing cohabitation patterns and rising incidence of sexually transmitted infections. Observed differences between Natsal 1990 and Natsal 2000 are likely to result from a combination of true change and greater willingness to report sensitive behaviours in Natsal 2000 due to improved survey methodology and more tolerant social attitudes.
authors.affiliation: Centre for Infectious Disease Epidemiology, Department of Primary Care and Population Sciences, Royal Free and University College Medical School, Mortimer Market Centre, WC1E 6AU, London, UK.
authors.forename: A M
authors.initials: AM
authors.lastname: Johnson
authors.forename: C H
authors.initials: CH
authors.lastname: Mercer
authors.forename: B
authors.initials: B
authors.lastname: Erens
authors.forename: A J
authors.initials: AJ
authors.lastname: Copas
authors.forename: S
authors.initials: S
authors.lastname: McManus
authors.forename: K
authors.initials: K
authors.lastname: Wellings
authors.forename: K A
authors.initials: KA
authors.lastname: Fenton
authors.forename: C
authors.initials: C
authors.lastname: Korovessis
authors.forename: W
authors.initials: W
authors.lastname: Macdowall
authors.forename: K
authors.initials: K
authors.lastname: Nanchahal
authors.forename: S
authors.initials: S
authors.lastname: Purdon
authors.forename: J
authors.initials: J
authors.lastname: Field
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D017280:Condoms / Q000706:statistics & numerical data; D005260:Female; D015658:HIV Infections / Q000635:transmission; D007722:Health Knowledge, Attitudes, Practice; D006801:Humans; D008019:Life Style; D008297:Male; D017533:Marital Status; D012307:Risk Factors; D017678:Sex Distribution; D012725:Sexual Behavior / Q000706:statistics & numerical data*; D011795:Surveys and Questionnaires; D006113:United Kingdom