(831) Assessment of Sexuality in Female Patients with Borderline Personality Disorder Using the ASEX and Mell-Krat Scales in Relation to the 2D:4D Digit Ratio

Introduction Borderline Personality Disorder (BPD) is a complex psychiatric condition characterized by instability in affect regulation, self-image, interpersonal relationships, and impulsivity. Growing evidence suggests that BPD may be associated with alterations in sexual behavior and attitudes, including increased sexual impulsivity, engagement in risky sexual practices, and difficulties in forming stable sexual relationships. These behavioral patterns may reflect underlying neurobiological and developmental factors that influence both personality organization and sexual functioning. The second-to-fourth digit ratio (2D:4D)-the relative length of the index (2D) and ring (4D) fingers-is considered a biological marker of prenatal androgen exposure, with lower ratios typically associated with higher levels of prenatal testosterone. This index has been linked to a range of behavioral, cognitive, and emotional traits, including impulsivity and sexual behavior. Investigating the 2D:4D ratio in female patients with BPD may therefore provide insight into the biological mechanisms underlying their sexual functioning and behavioral tendencies. Objective The present study aimed to assess sexual functioning in female patients with BPD and to explore its potential association with a biological marker of prenatal hormonal influence-the 2D:4D digit ratio. By integrating psychometric assessments of sexual functioning with a non-invasive biomarker, this research seeks to contribute to a more comprehensive understanding of the biopsychosocial mechanisms underlying sexual expression in women with BPD. Methods The study included 35 women diagnosed with BPD and 56 women in a control group. BPD diagnoses were established through clinical psychiatric evaluation and the Structured Clinical Interview for DSM-IV Axis II Disorders (SCID-II). Sexual response components were assessed using the Arizona Sexual Experiences Scale (ASEX) and the Mell-Krat Scale. The 2D:4D ratio was measured as an indirect indicator of prenatal exposure to testosterone and estrogen. Results Lower right-hand digit ratios were observed in the BPD group compared with the control group (0.989, SD = 0.034 vs. 1.016, SD = 0.038; U = 580.5; Z = 3.09; p = 0.002), suggesting higher prenatal testosterone exposure among women with BPD. Significant correlations were found between right-hand digit ratio and several aspects of sexual functioning within the BPD group, including “sexual arousal” (r = 0.406, p = 0.019) and “vaginal lubrication” (r = 0.306, p = 0.038) on the ASEX, as well as “sexual interest” (r = 0.379, p = 0.030) and “frequency of reaching orgasm” (r = 0.403, p = 0.020) on the Mell-Krat Scale. Conclusions Physiological components of sexual response-such as desire and arousal-in women with BPD appeared to be significantly and indirectly associated with higher prenatal testosterone levels, as inferred from lower 2D:4D digit ratios. These findings may point to a potential biological contribution to the sexual and behavioral characteristics observed in BPD. Disclosure No