The association between substance use, unplanned sexual intercourse and other sexual behaviours among adolescent students

Aims. To determine the prevalence of high-risk sexual behaviours and the in fluence of substance use and unplanned sexual intercourse on multiple sexua l partners, inconsistent condom use and reasons for not always using condom s among adolescent students. Design. A standardized self-reported anonymous questionnaire administered to a representative sample of students. Setting . The Canadian provinces of Nova Scotia, New Brunswick, Newfoundland and La brador, and Prince Edward Island in 1998. Participants. 9997 students in gr ades 9, 10 and 12 in the public school system. Measurements. Items on sexua l intercourse, unplanned sexual intercourse, number of sexual partners, con dom use, alcohol use, episodes of binge drinking and drunkenness, cigarette smoking and cannabis use. Findings. About 37.5% of males and 39.7% of fema les reported having engaged in sexual intercourse in the 12 months prior to the survey. Of those, 68.0% of males and 61.5% of females reported having engaged in unplanned sexual intercourse, 40.9% of males and 32.1% of female s reported having more than one sexual partner, and 49.9% of males and 64.1 % of females reported inconsistent condom use. Unplanned sexual intercourse under the influence of alcohol or other drug was found to be an independen t risk factor for multiple sexual partners and inconsistent condom use. Con clusion. The demonstration of an association between substance use, unplann ed sexual intercourse and other sexual behaviours lends support to a harm m inimization approach, including the provision of non-judgemental informatio n and interventions addressing unplanned sexual intercourse under the influ ence of a substance.