Prevention of fetal damage through dietary control of maternal hyperphenylalaninemia.

Maternal phenylketonuria is a new entity in obstetrics. If unrecognized and for this or other reasons untreated, it produces a substantial risk for fetal damage. Our knowledge of the pathophysiology of the fetal complications in maternal PKU is very limited, but the degree of maternal hyperphenylalaninemia seems to be important. The management differs from the other high-risk pregnancies in the need for a special diet beginning before conception. An effective program of dietary therapy designed in collaboration with a PKU clinic will reduce the likelihood of fetal damage and improve pregnancy outcome.