Gonads and strife: Sex hormones vary according to sexual orientation for women and stress indices for both sexes

This study assessed sexual orientation and psychobiological stress indices in relation to salivary sex hormones as part of a well-validated laboratory-based stress paradigm. Participants included 87 healthy adults that were on average 25 years old who self-identified as lesbian/bisexual women (n = 20), heterosexual women (n = 21), gay/bisexual men (n = 26), and heterosexual men (n = 20). Two saliva samples were collected fifteen minutes before and fifteen minutes after exposure to a modified Trier Social Stress Test to determine testosterone, estradiol, and progesterone concentrations via enzyme-immune assaying. Mean sex hormones were further tested in association to stress indices related to cortisol systemic output (area under the curve with respect to ground) based on ten measures throughout the two-hour visit, allostatic load indexed using 21 biomarkers, and perceived stress assessed using a well-validated questionnaire. Results revealed that lesbian/bisexual women had higher overall testosterone and progesterone concentrations than heterosexual women, while no differences were found among gay/bisexual men in comparison to heterosexual men. Lesbian/bisexual women and heterosexual men showed positive associations between mean estradiol concentrations and allostatic load, while gay/bisexual men and heterosexual women showed positive associations between mean testosterone and cortisol systemic output. In summary, sex hormone variations appear to vary according to sexual orientation among women, but also as a function of cortisol systemic output, allostatic load, and perceived stress for both sexes.