The knowledge about the risk of pregnancy in vasculitides mostly derives from single case reports or at best from retrospective studies with all the caveats that these observations include. Primary systemic vasculitides are uncommon, encompassing a broad spectrum of severity, from mild to life-threatening manifestations and with different natural histories, from self-limiting to relapsing or chronic active disease. The treatments require a cautious use of immunosuppressants tailored to each specific condition. Furthermore, most of the cytotoxic drugs necessary to treat vasculitis act by modifying the cell cycle and cell differentiation, biological effects that are particularly hazardous for the foetus. In order to have an uncomplicated pregnancy, conception should be planned when the disease is inactive. Moreover, organ failure or damage, due to previous disease activity, must also be taken into account since it can lead to adverse obstetrical and fetal outcomes.