Microcephaly

What is microcephaly?

Microcephaly is a rare neurological condition in which a baby’s head is much smaller than usual. Scientifically, this size is defined as less than 2 standard deviations below the average. It can be an isolated condition, without other major birth defects, or it can occur in combination with other major birth defects.

What causes microcephaly?

Microcephaly is caused by a baby’s brain not having been fully developed during pregnancy, damaged during pregnancy, or having stopped growing after birth, resulting in a smaller head size. The exact reason that this occurs is not completely known, but the following are some of the factors that have been known to play a causative role:

• Gene mutations
• Certain infections during pregnancy, such as rubella, toxoplasmosis, or cytomegalovirus
• Severe malnutrition
• Exposure to harmful substances, such as alcohol, drugs, or toxic chemicals
• Interruption of the blood supply to the baby’s brain during development
• Craniosynostosis

What are the symptoms of microcephaly?

Microcephaly has been linked to the following associated symptoms, and they can range from severe to more mild, depending on how small and underdeveloped the brain is:

• Seizures
• Developmental delay, such as problems with speech or other developmental milestones
• Intellectual disability
• Problems with movement and balance
• Feeding problems, such as difficulty swallowing
• Hearing loss
• Vision problems
• Backward-sloping forehead or other facial distortions

How is microcephaly diagnosed?

Microcephaly can be diagnosed during pregnancy using an ultrasound test in the third trimester or after the baby is born by measuring a baby’s head circumference during a physical exam and comparing this measurement to population sex and age standards. After diagnosis, imaging tests such as MRI scans can be used to provide information about the structure of the brain and the severity of the associated complications.

What are the available treatments for microcephaly?

Microcephaly is a lifelong condition, without any known cure or standard treatment, and since the microcephaly can range from mild to severe, treatment options can range as well. Corrective surgery can be used to treat craniosynostosis, and for severe microcephaly, patients will need treatment focused on managing the complications of the condition, such as developmental services and physical therapies. If seizures result, anticonvulsants can be taken.

Where can I find more information on microcephaly?

• Centers for Disease Control and Prevention (CDC)
• Mayo Clinic
• NIH