Bridging the Knowledge Gap: Assessing Adolescents’ Understanding of Sexually Transmitted Infections

Background: Sexually transmitted infection (STI) rates are rising as condom use declines, and adolescents are particularly vulnerable due to risk-taking behaviors and low testing rates.Aim: This study aimed to assess adolescents’ knowledge of STIs and their condom use practices in Portugal.Methods: A cross-sectional descriptive study was conducted at a level II hospital and a school in the Lisbon Metropolitan Area. Adolescents aged 13 to 18 years were invited to participate by anonymously completing a questionnaire. STI knowledge and attitudes were assessed according to sexual activity and gender using Chi-square or Fisher’s Exact tests.Results: 164 participants (mean age 16.1 years, ± 2.0 years), 54.3% female and 68.3% Portuguese, were included in the study. While most participants were familiar with the human immunodeficiency virus and herpes, knowledge of chlamydia, gonorrhea, trichomoniasis, and human papillomavirus was limited. Knowledge gaps included extragenital manifestations of STIs and their potential asymptomatic nature. Misconceptions involved transmission via shared bathrooms and the belief that the withdrawal method or contraceptive pills prevent STIs. Gaps were also identified in prevention in same-sex female relationships, oral sex, and the use of dental dams. Health professionals and digital platforms were the most frequently reported information sources. Among sexually active participants, 67.2% reported inconsistent condom use, citing discomfort and reduced pleasure as barriers. STI knowledge differed significantly by sexual activity and gender, with sexually non-active males being the most vulnerable to these knowledge gaps.Conclusions: The identified knowledge gaps and barriers to condom use emphasize the need for targeted educational strategies to improve STI awareness and prevention among adolescents.