What are your recommendations for management of patients with familial polycythemia due to EPOR mutation during pregnancy?

This is not a question that has a definitive answer since I know of no reports dealing directly with this uncommon situation and I have never treated such a patient. I have, however, successfully treated many pregnant vera patients, who have a constitutively-active erythropoietin receptor (EPOR) due to a different type of mutation, and I think that the same situation probably applies here. From several published pedigrees for this type of familial EPOR mutation, there appears to be hypersensitivity to very low levels of erythropoietin, fertility appears unimpeded and longevity is the rule, but in one pedigree there was unexplained childhood mortality. Headache appears to be the principal complaint, alleviated by phlebotomy.

The key to mana...