Successful management of a pregnancy with maternal phenylketonuria: report of a case.

Maternal phenylketonuria (PKU) is associated with significant complications such as mental retardation, microcephaly and congenital heart defects in nonphenylketonuric offspring. Dietary control with a low phenylalanine diet during the gestation period is effective in improving perinatal outcome in these cases. We present the case of a 27-year-old woman with classical features of PKU who had previously given birth to three babies, all of whom died of congenital heart disease. A low phenylalanine diet was started one month prior to the pregnancy and satisfactory fetal outcome was achieved.