While urticarial, PUPPP is specifically related to pregnancy, often starts within the abdominal striae, and is more persistent than typical acute urticaria.
BP can be triggered by pregnancy, but it is an autoimmune disease with large, tense bullae and is confirmed by immunofluorescence, whereas blisters are rare in PUPPP.
This is an autoimmune blistering disease of pregnancy, distinguished from PUPPP by its more common blistering, periumbilical onset (not within striae), and positive immunofluorescence findings.
