Background: In Portugal a large percentage of teens do not know any form of infection or treatment of sexually transmitted infections, making them vulnerable, because the consequences of untreated STI are severe and entail high health care costs.
Objectives: Analyze the influence of socio-demographic and contextual variables on knowledge about sexually transmitted infections.
Methods: A descriptive, non-experimental and cross-sectional study. The non-probabilistic convenience sample consists of 1216 adolescents attending the 9th year of studies in Portuguese Public Schools. They are all a part of the project PTDC/CPE-CED/103313/2008.
Results: The mean age was 14.69 years old; 12.6% had already initiated sexual intercourse; 48.1% have favorable attitudes towards sexuality; boys showed more favorable attitudes than girls, (X2 = 36,348, p = 0.000). There are statistically significant differences between sex, sexuality dialogue with teachers and health professionals (p = 0.000), age (p = 0.004) and attitudes of adolescents towards sexuality. Girls have more knowledge about sexually transmitted infections than boys with significant statistic differences (t = -5550; p = 0.000). As for the boys, the youngest (14 years old) are the ones with more knowledge about STIs (f = 7.700; p = 0.000). Globally, teenagers who do not date, that live in urban areas and those who have had sex have more knowledge but with no significant differences.
Conclusion: The results point to the need for effective and integrated sex education programs over an extended health education perspective on the gender variables, place of origin (rural and urban), dating, having sexual intercourse are considered in order of decrease adolescents’ vulnerability to sexually transmitted infections.
