Sex in Australia: contraceptive practices among a representative sample of women.

Objectives: To document the use of contraception by a representative sample of Australian women aged 16-59 years.
Method: Between mid-2001 and mid-2002, computer-assisted telephone interviews were completed by 9,134 women aged 16-59 years from all States and Territories selected by modified random-digit dialling of households (response rate 77.6%). Respondents were asked about contraceptive methods used in their current regular relationship(s) and during recent sexual encounters, or in general, or their reasons for non-use. Responses were allocated to 14 categories.
Results: 70.8% of respondents were using a method of contraception, over 95% of those apparently at risk of pregnancy. Most common reasons for non-use were not having intercourse (41.6%) and being past menopause (21.6%). Among those apparently at risk of unplanned pregnancy (i.e. who were heterosexually active and fertile but not pregnant or trying to become pregnant; 13.0% of non-users), the most common reasons for non-use were experience of side-effects or contra-indications (23.0%), leaving it to chance (20.2%), forgetting/not caring (18.9%), breast feeding (16.5%) and believing it unnatural/unhealthy (13.7%). No women cited religious objections or lack of access to services. The most used methods were oral contraceptives (33.6% of users), tubal ligation/hysterectomy (22.5%), condom (21.4%) and vasectomy of partner (19.3%). Tubal ligation rates were higher and condom use lower in regional and remote areas.
Conclusion: Given the high levels of use and knowledge and lack of evidence of unmet service need, most unplanned pregnancies in Australian adults are likely to be attributable to method failure or inconsistent use.