Medical quality assurance by Dr. Albrecht Nonnenmacher, MD at February 23, 2016

Microcephaly is a rare condition in which a baby is born with a head that is smaller than normal and suffers from brain development that is impaired. It is hard to pinpoint exactly what causes it, and once diagnosed, it can range from an inconvenience to a severe health issue. Treatment is available to help manage the condition, but there is no cure.


Definition & Facts

A congenital disorder, microcephaly affects only 2-12 babies per 100,000 in the United States and can be caused by a variety of factors. The head may have stopped growing in utero, or even after the birth of the child. It is possible that once diagnosed, it could be the only health issue a baby faces, or it could be one of a host of symptoms, reflecting a greater problem.

Symptoms & Complaints

There are many symptoms of microcephaly, including impaired cognitive development and various developmental delays like delayed motor skills (such as sitting, standing, and walking), delayed speech, facial distortions, dwarfism, hyperactivity, seizures, and difficulties with coordination and difficulties with balance. It is possible for a small amount of children with the disorder to not experience developmental disabilities, and some children's heads may even grow bigger, although this is rare.

Microcephaly can often be found in conjunction with other health problems, such as seizures, difficulty swallowing, hearing loss, and vision problems. These problems can range anywhere from mild to severe. They usually last a lifetime. Children with the more severe type require close follow-up from a healthcare provider to keep an eye on their development and growth.


The causes of microcephaly are unknown in most cases and occasionally the subject of controversy. Most often, the disorder is caused by abnormalities that interrupt the cerebral cortex's growth during early fetal development. The disorder is also associated with Down's syndrome, other chromosomal abnormalities, and neurometabolic disorders. If the mother abuses drugs or abuses alcohol during the pregnancy, microcephaly can be a consequence of conditions such as fetal alcohol syndrome.

Infections, such as chickenpox, rubella (also known as German measles), or Cytomegalovirus (a virus similar to the herpes virus), that the mother acquires or battles during a pregnancy are another cause. Phenylketonuria in the mother (a disorder that is caused by too much of a certain amino acid in the blood) or toxoplasmosis (a disorder that is mostly passed on to humans via cats/kitty litter) are other causes.

If a mother suffers from malnutrition, the child can suffer from this disease. Finally, exposure to certain toxic chemicals can cause the disease, and this is where the controversy arises. A new theory presented by doctors from Argentina believe that the recent increase in the disorder among children in Brazil is caused by a larvicide intended to decrease the mosquito population as opposed to the Zika virus which causes Zika fever a rarely deadly viral infection spread by mosquitoes that is characterized by flu-like symptoms and a rash.

Diagnosis & Tests

Microcephaly can be diagnosed in a child both before or after birth. During pregnancy, either late in the second trimester or the start of third trimester, an ultrasound technician will notice the small size of the head and notify a physician, who can then confirm the condition.

Once the baby is born, a physician can diagnose microcephaly by measuring his/her head circumference and comparing the results to the standard measurements for babies of the same age, sex, and size. In order for microcephaly to be diagnosed, the baby's head must be two standard deviations below the average. Severe microcephaly is described as the measurement being three standard deviations below the average.

If further confirmation is needed, a CT scan or an MRI can be performed to determine a diagnosis. Other methods a doctor might use to determine a baby's status are:

Treatment & Therapy

There is no cure for microcephaly, so if a child suffers from the disorder, his head can never return to normal size. Some cases are much more severe than others, therefore, the treatment options vary from case to case. Fortunately, the only problem that most of these babies will ever have is a small head, and these children's cases will only require periodic monitoring of their growth and development.

As for the more severe cases, parents and caregivers can provide treatment to help deal with delayed milestones and to maximize their potential given the presence of physical disability and intellectual disability. They will also need treatment for any of the other physical challenges they suffer in conjunction with the disorder.

Medications can help with certain issues that accompany microcephaly, such as seizures or digestive problems. In order to help these children maximize their potential, they will need to participate in speech therapy (therapy focused on helping patients speak more clearly) , occupational therapy (a type of therapy that encourages rehabilitation involving activities that a patient would perform in everyday life), and physical therapy (therapy that focuses on treatment through exercise).

If craniosynostosis (a premature fusing of the growth plates in the skull) is the cause of microcephaly, surgery can be performed to reshape the skull and allow for it to take a normal shape. In any other case, there is no surgery that can correct the disorder.

Prevention & Prophylaxis

There is really no sure way to prevent microcephaly in a baby. If it is determined to be the result of a genetic disorder, parents can discuss future pregnancy options with a geneticist. Otherwise, the best course of action is to control the factors that are controllable, such as not abusing drugs or alcohol during pregnancy, making sure that nutrition during pregnancy is adequate, and avoiding cat litter boxes during pregnancy in order to avoid toxoplasmosis.

Since preventable diseases, such as measles and chicken pox may be a factor, it is important to be current on vaccines in order to avoid these sicknesses during a pregnancy. Finally, avoiding toxic chemicals as much as possible is a smart course of action to ensure the health of the baby.