May also be called: Microcephalus

Microcephaly (my-kro-SEF-ah-lee) is a rare condition in which a child's brain does not fully develop, resulting in an abnormally small head size.

More to Know

Microcephaly, which can be passed down through families, can be present at birth or develop during the first 2 years of life. Chromosomal disorders (such as Down syndrome), metabolic disorders, bacterial meningitis, and lack of oxygen all can cause microcephaly. A baby is at increased risk if the mother used drugs or alcohol during her pregnancy or was exposed to chemicals, radiation, or certain viruses.

Some children with microcephaly will have no symptoms or developmental delays, and will be generally unaffected. Others will have varying degrees of developmental problems depending on what caused the microcephaly. They may have intellectual disabilities, delayed speech and motor functions, vision and hearing problems, dwarfism or short stature, seizures, or other problems associated with brain abnormalities.

Keep in Mind

There is no treatment for microcephaly that can reverse the problem. Children who have it can, however, benefit from early intervention programs with physical, occupational, and speech therapists to help them reach their full potential and enhance their quality of life.

All A to Z dictionary entries are regularly reviewed by KidsHealth medical experts.