SummaryConsecutive admissions of 214 women with borderline personality disorder were investigated for patterns of specific forms of self-harm and reported developmental experiences. Systematic examination of clinical notes found that 75% had previously reported a history of childhood sexual abuse. These women were more likely to self-harm, and in specific ways that may reflect their past experiences. Despite this, treatment within a dialectical behaviour therapy-informed therapeutic community leads to relatively greater clinical gains than for those without a reported sexual abuse trauma history. Notably, greater behavioural and self-reported distress and dissociation were not found to predict poor clinical outcome.Declaration of interestNone.Copyright and usage© The Royal College of Psychiatrists 2015. This is an open access article distributed under the terms of the Creative Commons Non-Commercial, No Derivatives (CC BY-NC-ND) licence.