In the worst cases, it can cause retardation or death.

At very high levels, it can cause anemia, kidney damage and mental retardation.

Carol had Phenylketonuria, a disorder that can cause mental retardation.

High levels can cause mental retardation, coma, convulsions and death.

Infants can be born with conditions that cause motormental retardation.

It can also cause mental retardation and sometimes crossed eyes as well.

Excessive drinking during pregnancy can cause mental retardation and physical problems with the child.

There's no evidence that the vaccine causes mental retardation.

If the Phe level gets too high, it can damage the brain and cause severe mental retardation.

It can cause seizures, mental retardation, or sight problems.