Open Neural Tube Defects (ONTDs) in Children
What are open neural tube defects in children?
Open neural tube defects (ONTDs) are problems with the way the brain, spinal cord,
or spine forms while a baby is growing in the pregnant person’s uterus. These problems
occur in about 1 in every 1,500 newborn babies each year.
The types of neural tube defects include:
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Spina bifida. This is when the spine doesn’t grow normally over the spinal cord. Babies born with
spina bifida may have minor or short-term problems. Or they may have lasting, serious
physical problems. These may include paralysis, lack of bowel and bladder control,
club feet, a buildup of spinal fluid in the head (hydrocephaly), and intellectual
disability. In most cases, a child may need surgery before or after birth. This is
the most common kind of ONTD.
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Anencephaly. This defect is when part of the brain and skull don’t form. It occurs when the neural
tube doesn’t close. Babies with anencephaly often die in the uterus after 20 weeks
of pregnancy (stillborn). Or they only live for a very short time after birth.
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Encephalocele. This is a very rare condition. With this defect, the brain or its coverings poke
through the skull. This can occur anywhere from the forehead to the lower back of
the skull. But it may also occur in the front of the skull, near the nose and sinuses.
In most cases, a child may need multiple surgeries after birth. Some encephaloceles
are very large. These are not able to be repaired without causing serious nervous
system problems.
What causes open neural tube defects in a child?
During pregnancy, the brain and spine begin as a flat plate of cells. This plate rolls
into a tube, called the neural tube. The tube is completely formed 28 to 32 days after
conception. If all or part of the neural tube fails to close, this leaves an opening.
The opening is called an open neural tube defect. The opening in the tube may be left
exposed or it may be covered with bone or skin.
Which children are at risk for open neural tube defects?
Neural tube defects are caused by genes passed on from both parents and from environmental
factors. Some of these factors include obesity, uncontrolled diabetes in the birth
parent, and some prescription medicines. In most cases, a child with a neural tube
defect has no family history of this problem. ONTDs happen 5 times more often in girls
than boys.
Once a child with a neural tube defect has been born in the family, the chance that
this problem will happen in another child rises to 1 in 25. The type of neural tube
defect can differ the second time. For example, a family's first baby could be born
with anencephaly. A second baby could have spina bifida instead.
Other risk factors for neural tube defects include:
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Mother’s age. Spina bifida is more common in teen mothers.
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History of miscarriage. A person who has had miscarriages in the past has a higher risk of having a baby
with neural tube defects.
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Birth order. Firstborn babies are at higher risk.
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Socioeconomic status. Children born into lower socioeconomic families are at higher risk for spina bifida.
Researchers think that poor diet may be a factor.
What are the symptoms of open neural tube defects in a child?
Symptoms depend on the type of ONTD. And they can occur a bit differently in each
child.
Symptoms of spina bifida can include:
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Area on the back that looks abnormal, such as a small hairy patch, dimple, or birthmark,
or a pouch-like bulge (sac)
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No feeling below the place on the spine where the sac is
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No ability to move the legs (paralysis)
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Constipation or incontinence
The baby may also have other problems such as:
Symptoms of anencephaly can include:
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No bones on the back of the head
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Missing bones on the front and sides of the head
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Large areas of brain missing
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Folding of the ears
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Bulging eyes
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Short or absent neck
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Split in the roof of the mouth (cleft palate)
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Congenital heart defects
Symptoms of encephalocele can include:
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Bulging sac at back of skull
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Face defects
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Fluid on the brain (hydrocephaly)
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Small head
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Weakness of arms or legs
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Trouble moving, walking, reaching
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Intellectual disability
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Vision problems
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Delayed growth and development
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Seizures
The symptoms of open neural tube defects can be like other health conditions. Make
sure your child sees their healthcare provider for a diagnosis.
How are open neural tube defects diagnosed in a child?
ONTDs can be diagnosed before birth with tests that include:
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Blood test. A test called a quad screen measures 4 substances in the mother's blood. This can
see if there is an increased risk for neural tube defects and other problems. This
test is done between 16 and 18 weeks of pregnancy. It measures levels of alpha-fetoprotein
(AFP) and other things in the blood. AFP is a protein made by the baby growing in
the uterus. If a baby has an open neural tube defect, the AFP level in the mother's
blood will be higher than normal. The test isn’t conclusive. This means it can’t prove
that your baby has an open neural tube defect. But it can show if your baby is at
risk for an ONTD. The test can show if you need more testing. The American College
of Obstetrics and Gynecology (ACOG) advises that this blood test be offered to all
pregnant women.
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Prenatal ultrasound. This imaging test uses high-frequency sound waves and a computer to make images of
blood vessels, tissues, and organs. Ultrasounds let healthcare providers see the internal
organs as they function. They also show blood flow through blood vessels. Prenatal
ultrasound may be able to find an open neural tube defect. Your provider may also
use ultrasound to look at some of the baby’s other organs and body systems.
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Amniocentesis. This test looks at a small sample of the fluid that surrounds the baby in the uterus.
The healthcare provider uses a long, thin needle to reach the amniotic sac. They take
the sample of fluid and check it for AFP. The test may not be able to find small or
closed defects.
After birth, a healthcare provider makes a diagnosis with a physical exam.
How are open neural tube defects treated in a child?
If your baby has an ONTD, you may need to have a cesarean section to deliver your
baby. This is often done to lower the risk for damage to the spinal cord that may
occur during a vaginal delivery.
If your child has spina bifida or encephalocele, they may need surgery to:
A baby may also need:
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Rehabilitation
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Positioning aids that help the child sit, lie, or stand
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Braces and splints that help prevent deformity and give support or protection to areas
of the body
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Medicines
Talk with your child’s healthcare providers about the risks, benefits, and possible
side effects of all treatments.
There is no cure or standard treatment for anencephaly. Treatment is supportive. This
means efforts are made to keep the baby as comfortable as possible. Anencephaly most
often leads to death in days or weeks.
What are possible complications of open neural tube defects in a child?
Babies with spina bifida are at high risk of developing a latex allergy. This is because
they are exposed to latex during the many medical and surgical procedures they need.
Your baby’s healthcare team will do their best to limit how much latex your baby is
exposed to. Your baby's healthcare providers can help you find out which products
contain latex and also find products that are latex-free.
Up to 3 in 4 babies with anencephaly are stillborn. Anencephaly most often leads to
death in days or weeks.
How can I help prevent open neural tube defects in my child?
The neural tube closes 28 to 32 days after a baby is conceived. This is before many
women know that they are pregnant. Normal development of the brain and spinal cord
may be affected during these first 3 to 8 weeks of pregnancy by:
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Not getting enough vitamins such as folic acid and other nutrients
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Infection
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Using prescription medicine or alcohol
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Being around hazardous chemicals and other substances
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Genetic problems
Folic acid is in prenatal vitamins. Getting this vitamin early in pregnancy is important
to prevent an ONTD. Researchers have found that a pregnant person who gets enough
folic acid (vitamin B-9) can help lower the risk for neural tube defects. Folic acid
is found in some leafy green vegetables, nuts, beans, citrus fruits, and fortified
breakfast cereals. Experts recommend that all people of childbearing age take a daily
multivitamin containing 400 to 800 micrograms of folic acid.
If you have had a child with a neural tube defect or are at high risk for ONTD, your
healthcare provider may recommend taking a larger amount of folic acid before your
next pregnancy. You may be directed to take 4,000 mcg of folic acid per day from 1
month before conception through the first 3 months of pregnancy, and 400 mcg a day
at other times, even when not planning on becoming pregnant. Discuss this with your
healthcare provider.
Your healthcare provider may also advise genetic counseling. You can talk with a counselor
about the risk of a neural tube defect in a future pregnancy. Also talk with your
provider about getting a prescription for folic acid to lower the risk for another
open neural tube defect.
How can I help my child live with an open neural tube defect?
Your child’s healthcare providers will work to prevent deformities or keep them to
a minimum. They will also work to help your child make the most of their capabilities.
Physical and occupational rehabilitation, plus extra support in school, can help a
child function as well as possible.
If your baby is born with an ONTD, there are things you can do to take care of yourself
and your baby:
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Keep all appointments with your baby’s healthcare provider.
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Talk with your baby’s healthcare provider about other providers who will be part of
your child’s care. Your child may get care from a multidisciplinary team that may
include counselors, social workers, genetic counselors, and physical or occupational
therapists. Your child’s care team will depend on your baby’s condition.
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Call your baby’s healthcare provider if you are concerned about your baby’s symptoms.
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Consider genetic testing and counseling to understand your risk.
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Tell others about your baby’s condition. Work with your child’s healthcare provider
to develop a treatment plan.
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Ask for support from local community services, such as your faith community, and organizations
that specialize in birth defects, such as the March of Dimes.
A diagnosis of anencephaly can be overwhelming and upsetting. You will face difficult
decisions about how to care for your baby. Many babies born with anencephaly may not
live beyond the first few days or weeks of life. Grief counseling may help you cope
with this loss.
When should I call my child’s healthcare provider?
Call the healthcare provider if your child has:
Key points about open neural tube defects in children
-
Open neural tube defects (ONTDs) are problems with the way the brain, spinal cord,
or spine forms while a baby is growing in the womb.
-
The types of neural tube defects include spina bifida, anencephaly, and encephalocele.
Treatment for an ONTD depends on the type of defect your child has.
-
Neural tube defects can be caused by genes passed on from both parents, nutrient deficiencies
in the birth parent, or environmental factors.
-
Symptoms can include a bulging sac on the back of the neck or head, or a very small
head.
-
Experts recommend that all women of childbearing age take a daily multivitamin containing
400 mcg of folic acid. Getting this vitamin early in pregnancy is important to prevent
an ONTD. People who have had a previous pregnancy affected by ONTD or who are at high
risk for ONTD should take 4,000 mcg of folic acid per day from 1 month before conception
through the first 3 months of pregnancy, and 400 mcg a day at other times, even when
not planning on becoming pregnant. Discuss this with your healthcare provider.
-
ONTDs can be diagnosed before birth with tests that include a blood test, prenatal
ultrasound, or amniocentesis.
Next steps
Tips to help you get the most from a visit to your child’s healthcare provider:
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Know the reason for the visit and what you want to happen.
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Before your visit, write down questions you want answered.
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At the visit, write down the name of a new diagnosis and any new medicines, treatments,
or tests. Also write down any new instructions your provider gives you for your child.
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Know why a new medicine or treatment is prescribed and how it will help your child.
Also know what the side effects are.
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Ask if your child’s condition can be treated in other ways.
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Know why a test or procedure is recommended and what the results could mean.
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Know what to expect if your child does not take the medicine or have the test or procedure.
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If your child has a follow-up appointment, write down the date, time, and purpose
for that visit.
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Know how you can contact your child’s provider after office hours. This is important
if your child becomes ill and you have questions or need advice.