Abstract | Gendered-based power affects heterosexual relationships, with beliefs in the U.S. prescribing that men dominate women sexually. We draw on social dominance theory to examine whether women's and men's level of support for group-based hierarchy (i.e., social dominance orientation; SDO) helps explain gender-based power beliefs and dynamics in heterosexual relationships. We conducted a laboratory study at a Northeastern U.S. university among 357 women and 126 men undergraduates who reported being heterosexual and sexually active, testing three sets of hypotheses. First, as hypothesized, women endorsed SDO and the belief that men should dominate sexually less than men did. Second, as hypothesized, among women and men, SDO was positively correlated with the belief that men should dominate sexually, and negatively correlated with sexual self-efficacy (confidence in sexual situations) and number of female condoms (a woman-controlled source of protection) taken. Third, structural equation modeling, controlling for age, family income, number of sexual partners in the past month, and perceived HIV/AIDS risk, supported the hypothesis that among women and men, the belief that men should dominate sexually mediates SDO's association with sexual self-efficacy. The hypothesis that the belief that men should dominate sexually mediates SDO's association with number of female condoms taken was supported for women only. The hypothesis that sexual self-efficacy mediates SDO's association with number of female condoms taken was not supported. Results suggest SDO influences power beliefs and dynamics in heterosexual relationships. Although female condoms are an important woman-controlled source of protection, power-related beliefs may pose a challenge to their use. |