Self-reported gonadal pubertal timing predicts adolescent borderline personality symptoms: two extended replications with prospective and cross-sectional data

The current study investigated the understudied relationship between pubertal timing and borderline personality disorder (BPD) symptoms in males and females. We conducted hierarchical linear regressions in a longitudinal Cohort 1 (N = 117) and a cross-sectional Cohort 2 (N = 127). Cohort 1: Pubertal timing was self-reported at age 10; BPD symptoms and covariates were assessed between ages 13 and 19. Cohort 2: All assessments were between ages 8 and 12. Covariates: race, age, internalizing and externalizing symptoms, and income-to-needs ratio. Sex differences were examined post hoc. In Cohort 1, early gonadal timing was associated with more BPD symptoms in females (beta =.46, p =.002), and late gonadal timing was associated with more BPD symptoms in males (beta = -.23, p =.035). In Cohort 2, early gonadal timing was associated with more BPD symptoms (beta =.21, p =.033) without sex moderation. Results indicate that early gonadal development could be a risk indicator for the emergence of BPD in adolescence, particularly in females, which could inform causal mechanisms and intervention targets.