In India, a substantial proportion of adolescents are sexually active, highlighting the crucial need for comprehensive sex education. The Adolescent Education Program (AEP), a nationwide sex education initiative launched in late 2006, aimed to address this need. However, facing significant opposition, the program was subsequently banned in eight states. This study investigates the impact of these bans on key sexual and reproductive health (SRH) outcomes among adolescent women aged 15–19. Using a difference-in-difference (DID) approach with nationally representative data from the National Family Health Survey (NFHS) Rounds 3 (2005-06), and 4 (2015-16), we examine the effects of the AEP ban on contraceptive usage and AIDS knowledge. Our findings reveal that the ban led to a substantial and significant decrease in contraceptive use and in AIDS knowledge. These negative impacts were disproportionately larger for adolescents from disadvantaged backgrounds. This study provides robust evidence for the vital role of comprehensive sex education in promoting adolescent SRH and underscores the potential for policy bans to exacerbate existing health disparities. Investing in and expanding access to programs like the AEP is crucial for protecting the health and well-being of vulnerable young people.