Caesarean scar endometriosis: how to make an accurate diagnosis.

Caesarean scar endometriosis is a rare condition characterised by the presence of endometrial tissue within a surgical scar following a caesarean section. A woman in her late 30s presented with a painful lump beneath her caesarean section skin scar, worsening during menstruation. Despite a previous incision and drainage procedure for a 'scar abscess', the symptoms persisted.