Gender inequity negatively affects health in Central America. In 2011, we conducted 60 semistructured interviews and 12 photovoice focus groups with young coupled men and women in León, Nicaragua, to explore the ways in which social norms around marriage and gender affect sexual health and gender-based violence. Participants’ depictions of their experiences revealed gendered norms around infidelity that provided a narrative to justify male expressions of jealousy, which included limiting partner autonomy, sexual coercion, and physical violence against women, and resulted in increased women’s risk of sexually transmitted infections, including HIV. By understanding and taking account of these different narratives and normalized beliefs in developing health- and gender-based violence interventions, such programs might be more effective in promoting gender-equitable attitudes and behaviors among young men and women in Nicaragua.