Depends amt. of nf
Congenital generalized (disseminated) neurofibromatosis
(detected prenatally) is associated with a poor prognosis, with a mortality rate of 92%.
Survival rates for patients detected before and after birth were 28% and 62%.However most cases of nf are focal and not disseminated without evidence of increased infantile mortality rate. In people with nf the overall decrease in life span is about 8 yrs.