Hormones and Borderline Personality Features.

Borderline personality is diagnosed in clinical settings three times more often in women than in men, and symptom severity in women appears sensitive to circulating sex steroid levels. In non-human mammals, prenatal hormones contribute to the development of sex-linked behavior and their responsiveness to postnatal hormones. Therefore, this study examined the hypothesis that prenatal hormones may influence the development of borderline personality traits by measuring a marker of perinatal androgen action, the 2D:4D ratio, and salivary hormone levels in 58 men and 52 women. Participants completed the Borderline Features Subscales (BOR) of the Personality Assessment Inventory, gender role questionnaires, and four sex-linked cognitive tasks. Digit ratios were a significant predictor of the affective component of borderline personality, such that in both sexes 2D:4D ratios suggestive of weaker perinatal androgen action contributed to greater borderline personality features overall and greater affective instability. In addition, women reporting greater affective instability showed larger changes in estradiol across the session, consistent with the influence of stress and emotional reactivity on hormonal function. These findings are consistent with an increasing body of research suggesting that hormonal factors associated with the expression of typical gender-linked behavior may also contribute to the expression of gender-linked maladaptive behavior.