Adolescent reproductive health (ARH) programmes in Nigeria have been implemented to improve knowledge, attitudes, and behaviors related to sexual health among young people. The study employed a longitudinal qualitative approach using participant observation, interviews, and focus group discussions in urban settings across Nigeria. Data collection occurred over three years, capturing pre-, mid-, and post-programme phases. During the follow-up phase, participants demonstrated significant improvement in knowledge about contraception methods (increased from 40% to 75%) and reduced intentions for early sexual activity (decreased by 25%). ARH programmes have successfully enhanced adolescent reproductive health literacy over time. Continued support is recommended to sustain these positive changes, particularly in marginalized communities where access remains limited.