Final answer:
Babies exposed to excess phenylalanine in-utero may develop heart defects, physical and/or intellectual disabilities, and microcephaly.
Step-by-step explanation:
PKU, or phenylketonuria, is a genetic disorder that affects around 1 in every 15,000 births in the United States. People with PKU lack the enzyme phenylalanine hydroxylase, which is needed to break down phenylalanine. If a pregnant person with PKU is not following a strict low-phenylalanine diet, excess phenylalanine can cross the placenta and affect fetal development.
Babies exposed to excess phenylalanine in utero may develop heart defects, physical and/or intellectual disabilities, and microcephaly. Therefore, it is crucial for pregnant individuals with PKU to closely monitor their diet and avoid foods high in phenylalanine, including artificial sweeteners and certain animal products and starches.