this article calls attention to factors associated with sexual and reproductive behavior among adolescents from the northeast and southeast regions of brazil. the analyses focus on three dimensions of this process: sexual initiation, use of contraceptives in the first sexual relationship, and fertility. hierarchical models are implemented, because adolescents selected from the same community are more likely to have similar sexual and reproductive behavior than those from different communities. level of schooling was the most important risk factor in the three analyses. girls with 5 or more years of schooling were less likely to have their first sexual relationship during adolescence and more likely to use contraceptive methods in this relationship, besides demonstrating less risk of having children than their counterparts with less than 5 years of schooling.