Five.

Self-harm.

Suicidal behavior and deliberate self-harm is common in people with BPD. Suicidal behavior includes thinking about suicide, making suicidal gestures or threats, or actually carrying out a suicide attempt. Self-harm encompasses all other attempts to hurt yourself without suicidal intent. Common forms of self-harm include cutting and burning.

HelpGuide.org

Self-harming behavior, such as cutting. Recurring thoughts of suicidal behaviors or threats.

NIMH

Suicidal threats or behavior or self-injury, often in response to fear of separation or rejection.

Mayo Clinic

Self-harming behavior including suicidal threats or attempts.

NAMI

This is one of nine traits used to diagnose borderline personality disorder. Many are common to other disorders, and you should seek professional guidance (if accessible) if you are concerned about a diagnosis.