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. Conclusion: 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.