What is Microcephaly?

3. What Causes Microcephaly?

This condition results from abnormal brain development either in the womb or during infancy. Other causes include genetics, chromosomal abnormalities, decreased oxygen, exposure to toxic chemicals, alcohol, or drugs, severe malnutrition, certain viral infections, or premature fusing of the infant’s skull. A mother's uncontrolled phenylketonuria—a condition that affects the body’s ability to break down the amino acid phenylalanine—can also cause microcephaly. An autosomal recessive disorder, it occurs when an individual has two copies of the faulty gene—one from each parent.