First sexual intercourse and contraception: a cross-sectional survey on the sexuality of 16-20-year-olds in Switzerland

Background: The onset of sexual activity represents an important developmen t stage with positive aspects, such as love, discovery, intimate relationsh ips, plans for the future, but also with fears of pregnancy, of sexually tr ansmitted diseases and of AIDS. Objective: To study perceptions, attitudes, and behaviour related to sexual life, AIDS and contraception; to explore the onset of first sexual relatio nships and the process of choice of a contraceptive method by the adolescen ts, in order to improve prevention programmes for young people. Method: Analysis of data from a Swiss national survey on adolescent sexuali ty using a computerised self-administered questionnaire, involving 2075 gir ls and 2208 boys between the ages of 16 and 20. The use of computers helps improve confidentiality, response rates and acceptability since survey ques tions are limited to the subjects' sexual experience only. Results: The young people's responses emphasised the importance of emotion in sexual relationships, girls choosing intimacy and fidelity while boys at tached more importance to physical pleasure. Three out of four respondents have had a sexual experience and one out of two have had penetrative sexual intercourse. The percentages of condom or oral contraception use are high: at first sexual intercourse, 86.5% used one or the other, while 7.4% did n ot declare any contraceptive method. The percentages are lower when age at first intercourse is below 15 years, when a girl had an older partner (age difference 7 years and more) and when the Ist relationship is a casual one. During their first stable relationship 41.1% of girls and 30.9% of boys sa y they have changed their contraceptive method from condom to contraceptive pill, 2.4% of girls and 2.9% of boys say they have given up any form of co ntraception. Among girls, condom use at first sexual intercourse with a new partner decreases in favour of oral contraception between first and last s teady relationships (75.6 vs 58.0%, p <0.05), the decrease being insignific ant between the first and last casual relationships (73.5 and 62.2%, n.s.). Among boys the rates of condom use are equal at first intercourse with the first and last partner (steady relationship: 74.1 and 77.2%; casual relati onship:78.3 and 76.2% respectively). Conclusion: The use of condoms is high among Swiss adolescents, particularl y at first sexual intercourse. By integrating the prevention of sexually tr ansmitted diseases and of unwanted pregnancies, preventive programmes would address adolescents' needs more effectively.