How would you manage post-transplant erythrocytosis in the setting of active pregnancy which limits use of ACEi/ARB therapy?  

Patient had a renal transplant and had been well controlled previously on ACEi/ARB therapy, but is now in her first trimester of pregnancy. Therapeutic phlebotomies have been trialed and are limited by severe recurrent iron deficiency. Would you consider hydroxyurea or interferon?