Introduction Youth STD/HIV information seeking and policy changes (e.g. same-sex marriage) may vary by sociocultural context. We used state-level same-sex marriage laws in the United States (US) as proxy measure for sociocultural context to examine sources of STD/HIV information among youth within different contexts.

Methods We used Westlaw to collect 2013 US state-level laws related to same-sex marriage as a proxy for state sociocultural context related to STD/HIV. Same-sex marriage laws were coded as 1) prohibited -– explicitly bans same-sex marriage (n = 34), 2) not addressed – does not mention sex (n = 11), 3) recognised – explicitly permitted (n = 6). Laws were merged with data from a 2013 US survey of 15–25 year olds (n = 4017) to assess sources of STD/HIV information among youth living in different sociocultural contexts.

Results Information sources for whether to have sex differed by sociocultural context. Youth living where same-sex marriage was recognised were more likely to report the following sources: doctor (54.9%, p < 0.0001), social media (15.5%, p < 0.01), and television/radio (25.0%, p < 0.01); those living where same-sex marriage is prohibited (26.4%) or not addressed (26.3%) had the highest reports of religious institutions as a source. Traditional information sources (parent, doctor, school,  religious institutions) about sexual relationships also differed by context; however, technological sources did not differ (internet, online expert, social media or television/radio). Those living where same-sex marriage was prohibited had the highest reports of parents (p < 0.01), religious institutions (p < 0.05) and magazines (p < 0.05) as STD/HIV information sources. Youth living where same-sex marriage was recognised had the highest reports of using social media for STD information (p < 0.05). Finally, for information on preventing STD/HIV during sex, respondents where same-sex marriage is not addressed were least likely to report social media as a source (p < 0.05).

Conclusion Readily available policies may be a useful proxy measure of sociocultural context in the field of STD/HIV prevention.