First vaginal intercourse and oral sex among a representative sample of Australian adults: the Second Australian Study of Health and Relationships.
Background Current information about the characteristics of Australian adults' first vaginal intercourse and contraception or precautions used on that occasion is needed, as well as whether these characteristics have changed between 2001-02 and 2012-13.


METHODS
Computer-assisted telephone interviews were completed by a representative sample of 20094 men and women aged 16-69 years. The overall participation rate among eligible people was 66.2%. Respondents indicated their age at first vaginal intercourse and first oral sex. Those who reported vaginal intercourse were asked the age of their partner, their relationship to their partner, the duration of this relationship, and what contraception or precautions (if any) were used.


RESULTS
There was a significant decline in the median age of first vaginal intercourse for both men and women among those born between the 1940s and the 1960s, but no further decline since. There has also been a significant increase in the use of protection at first vaginal intercourse, from less than 20% of men and women in the 1950s to over 90% in the 2000s. For men and women, first vaginal sex before age 16 years was significantly associated with a greater number of lifetime and recent sexual partners, and a greater likelihood of having had a sexually transmitted infection.


CONCLUSIONS
Given the earlier age at first vaginal intercourse, sex education should begin earlier so that all young people have information about contraception and disease prevention before they begin their sexual careers.
Sydney School of Public Health, Charles Perkins Centre (D17), University of Sydney, Sydney, NSW 2006, Australia.
Chris
C
Rissel
Australian Research Centre in Sex, Health and Society, La Trobe University, 215 Franklin Street, Melbourne, Vic. 3000, Australia.
Wendy
W
Heywood
School of Psychology, Pevensey 1, University of Sussex, Falmer BN1 9QH, UK.
Richard O
RO
de Visser
Sydney School of Public Health, Edward Ford Building (A27), University of Sydney, Sydney, NSW 2006, Australia.
Judy M
JM
Simpson
The Kirby Institute, Wallace Wurth Building, University of New South Wales, Sydney, NSW 2052, Australia.
Andrew E
AE
Grulich
Australian Research Centre in Sex, Health and Society, La Trobe University, 215 Franklin Street, Melbourne, Vic. 3000, Australia.
Paul B
PB
Badcock
Australian Research Centre in Sex, Health and Society, La Trobe University, 215 Franklin Street, Melbourne, Vic. 3000, Australia.
Anthony M A
AM
Smith
The Kirby Institute, Wallace Wurth Building, University of New South Wales, Sydney, NSW 2052, Australia.
Juliet
J
Richters