Why do heterosexual young adults who use reliable contraception also use condoms? Results from a diary-based prospective longitudinal study.

OBJECTIVES: To identify characteristics of individuals and characteristics of sexual encounters that predict whether people using contraception will also use condoms (dual use), and to determine whether dual use is prompted by concerns about unplanned pregnancy and/or sexually transmitted infections (STIs).
DESIGN: A longitudinal prospective design was used to identify characteristics of individuals and characteristics of specific sexual encounters that predict condom use.
METHODS: A sample of 349 sexually active heterosexual young adults was recruited at universities and trade colleges in Melbourne, Australia. Participants completed a self-administered questionnaire, and a representative subsample (N=103) completed a structured condom use diary in which they reported on up to 10 instances of vaginal intercourse. Respondents reported use of condoms and other forms of contraception during 919 instances of vaginal intercourse.
RESULTS: In multivariate analyses, dual use of condoms in addition to other contraception was predicted by attitudes toward condoms, intentions to use condoms, partner type and discussion of condom use with sexual partners. Dual use was not related to greater concern about HIV/STIs or unplanned pregnancy.
CONCLUSIONS: Encouraging heterosexual young adults to discuss condom use, and developing their skills for negotiation of condom use will increase rates of condom use, thereby reducing current high rates of unplanned pregnancy and STIs.