 [ Symptoms ] what is the differential diagnosis for someone who cuts their face a female teenager who is suicidal my question is this is an unusual behavior for a borderline diagnosis it seems to indicate psychosis [ Disease ] it would be highly unlikely that pregnancy could occur from the scenerio that you described there are many things that cause a delay in the menses including stress because you both are engaging in intimate sexual activity it may only be a matter of time before you both decide to go the rest of the way and have vaginal sex i would strongly suggest that you use condoms and that your girlfriend be on another form of effective birth control