biostudies-literatureUnknown54(8)Kennair LEONTNU Norwegian University of Science and TechnologyA robust, cross-cultural sex difference is typically found in jealousy responses to reveal emotional versus sexual infidelity. The only factor that seems to moderate this sex difference is sexual orientation, with male heterosexuals conspicuously reporting the greatest distress to sexual infidelity. Attempts at considering additional effects of psychological feminization and masculinization on jealousy responses have proven less reliable. In a sample of 4465 participants aged between 16 and 80 years (M = 35.41, SD = 13.07), including gay, lesbian, heterosexuals, bisexuals, and pansexuals, we examined how four indicators of feminization-masculinization were associated with sexual orientation and, subsequently, to jealousy responses to infidelity. We found that an exclusive gynephilic orientArchives of sexual behavior3189-3203https://www.ebi.ac.uk/biostudies/studies/S-EPMC12484348biostudies-literatureMale Sex, Masculinization, Sexual Orientation, and Gynephilia Synergistically Predict Increased Sexual Jealousy.PMC12484348Kennair LEOSchmitt DPBendixen MfalseMale Sex, Masculinization, Sexual Orientation, and Gynephilia Synergistically Predict Increased Sexual Jealousy.A robust, cross-cultural sex difference is typically found in jealousy responses to reveal emotional versus sexual infidelity. The only factor that seems to moderate this sex difference is sexual orientation, with male heterosexuals conspicuously reporting the greatest distress to sexual infidelity. Attempts at considering additional effects of psychological feminization and masculinization on jealousy responses have proven less reliable. In a sample of 4465 participants aged between 16 and 80 years (M = 35.41, SD = 13.07), including gay, lesbian, heterosexuals, bisexuals, and pansexuals, we examined how four indicators of feminization-masculinization were associated with sexual orientation and, subsequently, to jealousy responses to infidelity. We found that an exclusive gynephilic orient2025-01-01T00:00:00Z2025 Aug2026-06-04T01:31:39.362Z2026-05-03T03:14:06.119ZS-EPMC124843484084724710.1007/s10508-025-03225-z