[Contraceptive use among adolescents at public schools in Brazil].

OBJECTIVE There has been a growing interest in patterns of contraceptive use among adolescents, due, in particular, to the social relevance attached to pregnancy in this age group. Therefore, the objective of the study was to investigate factors associated with the use of contraceptive methods among female and male adolescent students. METHOD A cross-sectional study was conducted, by means of self-applied questionnaires, among 4,774 students ranging from 11 to 19 years of age. Prevalence with respect to the use of contraceptive methods during the first experience of sexual intercourse as well as the most recent one was calculated both separately, that is, for each of these events, and in conjunction as a measure of consistent use. Logistic regression was carried out for simultaneous analysis of factors associated with the use of contraceptive methods and in order to calculate adjusted measures. RESULTS Among the 1,664 students who reported being sexually active, the factors positively associated with the consistent use of contraceptive methods among male students included a) postponing their first experience of sexual intercourse and interaction with a stable partner, b) the family as a potential supplier of contraceptive methods, and c) access to health services. On the other hand, among female students factors positively associated with the consistent use of contraceptive methods included a) recent sexual initiation, and b) having a father as their source of information regarding sexuality, contraception and STD/AIDS prevention. Pregnancy was reported by 6.4% of the boys and 18.1% of the girls, its absence was associated with the consistent use of contraceptives by them (the girls) (Odds Ratio=3.83; 2.06-7.15). CONCLUSIONS The results confirm the complexity of determining contraceptive behavior among adolescents and therefore reinforce the need to include multi-dimensional aspects of this theme in order to ensure the efficacy of sex education programs.