Microcephaly in children

At Children’s Health℠, we treat all types of microcephaly (mi·​cro·​ceph·​a·​ly) during your pregnancy, the postnatal period and beyond. Doctors all over North Texas – and even outside the state – refer families to us for our expertise in treating babies and children with microcephaly. Our goal is to help every child with microcephaly reach their full potential.

What is microcephaly in children?

Microcephaly is a rare condition that occurs when a baby’s head and brain are smaller than normal for the baby’s age. It can result from infections or very rare genetic syndromes.

Microcephaly comes from “micro,” meaning small, and “cephaly,” meaning head. The term describes a baby’s head that is smaller than expected compared to other babies of the same gender, ethnic background and age.

The size of a baby’s head is largely determined by brain growth. If something causes a baby’s brain to develop abnormally in the womb, the baby's head may be smaller than is typical.

A smaller brain can cause developmental and intellectual difficulties. Microcephaly can range from mild to severe.

What are the signs and symptoms of microcephaly in children?

In most cases, the only early sign of microcephaly is a small head (skull) size.

Other symptoms include:

  • Feeding difficulties or failure to thrive
  • Hearing and vision problems
  • High-pitched crying
  • Movement and balance problems
  • Seizures or muscle spasm

Many babies born with microcephaly don’t have any other symptoms at birth.

Later in life, they may develop complications such as:

How is microcephaly in children diagnosed?

During pregnancy

Most commonly, your OB-GYN diagnoses microcephaly during your pregnancy, at an 18 to 20-week ultrasound scan. During this scan, the sonographer takes detailed measurements of your baby’s anatomy and compares them to expected standards.

After birth

In some cases, microcephaly develops after birth. Pediatricians and other providers track your baby’s growth and development. By measuring your child’s head size at each well-child visit over the first few years of life, a pediatrician can detect microcephaly that occurs during early childhood.

Your child’s pediatrician will also take into account if:

  • The head is proportionate to the baby’s body size
  • Other family members have a smaller head size
  • Your child has other abnormalities, such as vision impairment, seizures or developmental delay

To diagnose the cause of the microcephaly, your child’s doctor may order tests such as:

Genetic testing for microcephaly in children

If other family members have microcephaly, we may recommend genetic testing to understand the cause. Certain syndromes are recessive, meaning that a baby inherits one gene from each parent. The syndrome doesn’t affect mom or dad, but when those two genes come together in a baby, they can cause disease. These syndromes are some of the most common ways for a child to inherit microcephaly.

At Children’s Health, we may perform genetic testing called a chromosomal microarray. This test examines your baby’s DNA for common disorders that can cause microcephaly. Your family can meet with a pediatric geneticist and genetic counselors to discuss appropriate screening tests. They also discuss your future family planning and other considerations that might be important for your family.

What causes microcephaly in children?

Microcephaly itself is not a disease. Instead, it is a sign of another underlying problem.

In many cases, no one will ever know what caused microcephaly in a child. It’s not usually due to anything you did or didn’t do as a parent.

Genetic causes

The primary cause of microcephaly may be an inherited genetic condition (congenital microcephaly). Many of these conditions are very rare. Families usually don’t even know they have the gene.

These include:

  • Inherited chromosomal abnormalities, including Down syndrome
  • Microcephaly vera disorder, a type of autosomal recessive disorder (a child inherits two genes with the mutation)
  • Rett syndrome
  • Other neurodegenerative disorders

Causes during pregnancy

  • Cerebral anoxia, which is decreased oxygen to the baby’s brain
  • Craniosynostosis, when plates in the skull close too early
  • Drug or alcohol exposure, especially alcohol, cocaine or opiates
  • Exposure to toxins or hazardous chemicals
  • Infections in the pregnant mother, such as chicken pox (varicella), cytomegalovirus (CMV), HIV, rubella (German measles), syphilis, toxoplasmosis or Zika
  • Maternal health problems, like severe malnutrition or untreated PKU (phenylketonuria)

Conditions after birth (acquired microcephaly)

How is microcephaly in children treated?

At Children’s Health, we treat babies with microcephaly in utero (before birth) or after birth.

Care during pregnancy

If we learn your baby has microcephaly in utero, we refer you to our Fetal Evaluation and Treatment Alliance (FETAL) Center.

You’ll have access to prenatal consultants from a wide variety of medical specialties including:

We can arrange for a fetal MRI imaging exam. Fetal MRI provides highly sensitive 3D imaging of your baby’s head and brain to confirm a diagnosis.

Care at birth and beyond

Our neonatal neurology doctors meet your baby right after birth, in the nursery or pediatric NICU. We follow your baby’s care long-term in our outpatient clinic. Throughout your baby’s life, we provide holistic, family-centered care.

If your baby has related conditions, we offer treatment for those problems, such as:

  • Seizures. We treat seizures with medications and state-of-the-art alternative treatments such as a ketogenic diet, vagal nerve stimulation or cannabidiol. Our pediatric neurology group includes epileptologists (doctors specially trained in neurology and treating and evaluating epilepsy). If a child isn’t responding to multiple medications and treatments, we may refer them to our Pediatric Epilepsy Center for evaluation.
  • Hearing loss and vision problems. Specialists offer therapies to optimize your child’s development in these areas.
  • Developmental delays. Neurologists may recommend therapies to improve your child’s development and help them walk, talk, interact with others and learn self-help skills.

In most cases, microcephaly has no specific treatment.

Microcephaly surgery

In some children, microcephaly happens because the skull bones close too early or fuse together. We can refer your family to our craniofacial and plastics specialists to discuss your options. These surgeons specialize in reconstructive surgery. They can perform procedures to help separate fused bones, so your child’s head and brain have room to grow.

Advanced microcephaly care

Through Children’s Health’s partnership with the research scientists at UT Southwestern, we can offer families access to highly sophisticated gene therapy and research options. In some cases, we have been the first in the world to pioneer these gene therapies.

Our team works together to understand the mechanism of what’s causing microcephaly and related disorders. Then we develop new treatments to create research trials where families can access those treatments.

Microcephaly in children doctors and providers

Children’s Health offers a team of pediatric brain specialists that’s unique in North Texas. Our doctors are also on the faculty of UT Southwestern.

Frequently Asked Questions

  • How common is microcephaly?

    In the United States, about 2 to 12 in 10,000 babies are born with microcephaly. That’s fewer than 1% of U.S. births.

  • Can microcephaly be prevented?

    Because doctors sometimes don’t know what causes microcephaly, you can’t always prevent it. And even with precautions, infections still happen. But you may reduce your chances of having a baby with microcephaly if you:

    • Avoid misuse of alcohol and drugs. Don’t smoke, drink or use street drugs right before or while you are pregnant. And don’t use prescription drugs without discussing their effects on pregnancy with your provider.
    • Protect yourself from Zika. The Texas Department of State Health Services tracks Zika danger in Texas. In most years, Zika is not a major concern here, but you should take precautions during mosquito season. Before traveling during pregnancy, check the Centers for Disease Control and Prevention (CDC) website for areas where Zika might be more active.
    • Try to prevent infections. Take routine precautions, such as handwashing, avoiding sharing drinks and practicing safe sex. Get dental cleanings to prevent gum infections. And don’t eat undercooked or raw foods.
    • Don’t change the kitty litter. Toxoplasmosis can be a risk factor for microcephaly. In the U.S., it’s most present in cat feces. Have someone else change the cat box while you are pregnant.
    • Speak to a geneticist. If you have a family history of microcephaly, you may wish to have genetic testing and genetic counseling when you are planning your family.
  • How do I know if my child has microcephaly or just a small head?

    The best way to know definitively if your child has microcephaly or just a small head is to ask your pediatrician. Your doctor can easily measure your baby’s head and let you know if they meet the criteria for microcephaly.

  • What should we know about my child’s physical appearance with microcephaly?

    It’s natural to worry about how microcephaly could affect your child’s self-esteem and confidence later in life. In more severe cases, your child’s head may be severely disproportionate. And for any child with microcephaly, their head size is always going to be smaller than expected.

    Depending on the underlying cause of microcephaly, the head size and brain will continue to grow. Eventually, the head size may even reach a typical part of the growth curve, although it will likely always be on the smaller side. Remember, too, that as your baby grows, they will grow a lot of hair, which also helps the head look more proportionate.