Anencephaly

Anencephaly is a serious birth defect that occurs when the brain and skull of a developing fetus do not form properly. It is a type of neural tube defect (NTD), which affects the development of the brain, spine, and spinal cord.

Causes and Risk Factors

Anencephaly occurs during the third to fourth week of pregnancy, when the neural tube fails to close completely. The exact cause of anencephaly is not known, but it is believed to be related to a combination of genetic and environmental factors. Women who are pregnant or planning to become pregnant can reduce their risk of having a child with anencephaly by taking folic acid supplements before and during early pregnancy.

Characteristics and Symptoms

Babies born with anencephaly often have:

  • Absent or partially absent skull and brain
  • Exposure of the brain tissue and membranes
  • Abnormal appearance of the head and face
  • Lack of reflexes and response to stimuli
  • Seizures and other neurological problems

Diagnosis and Testing

Anencephaly can be diagnosed during pregnancy through:

  • Ultrasound imaging: to visualize the fetus's brain and skull
  • Magnetic resonance imaging (MRI): to provide more detailed images of the fetus's brain and skull
  • Maternal serum screening: to measure the levels of certain substances in the mother's blood that may indicate an increased risk of NTDs
  • Amniocentesis: to analyze the fluid surrounding the fetus for genetic abnormalities

Treatment and Prognosis

There is no cure or treatment for anencephaly. Most babies born with anencephaly do not survive for more than a few days or weeks after birth. In some cases, the baby may be stillborn or die shortly after delivery. For those who do survive, the prognosis is generally poor, and they often require extensive medical care and support.

Prevention

To reduce the risk of having a child with anencephaly, women can take the following steps:

  • Take folic acid supplements before and during early pregnancy (400-800 micrograms per day)
  • Maintain a healthy diet and lifestyle
  • Avoid exposure to toxins and substances that may increase the risk of birth defects

Support and Resources

Families affected by anencephaly can find support and resources through various organizations, such as:

  • The National Institute of Neurological Disorders and Stroke (NINDS)
  • The Centers for Disease Control and Prevention (CDC)
  • The March of Dimes
  • Local hospitals and healthcare providers

Frequently Asked Questions (FAQs)

What is anencephaly?
A rare congenital disorder where a baby is born without parts of the brain and skull.

What causes anencephaly?
Neural tube defect due to genetic or environmental factors during pregnancy.

Is anencephaly inherited?
Usually not, but family history may increase risk.

Can anencephaly be prevented?
Folic acid supplements before conception may reduce risk.

How is anencephaly diagnosed?
Ultrasound scan during pregnancy.

What are the symptoms of anencephaly?
Absent or partially absent brain and skull.

Is anencephaly compatible with life?
Most babies with anencephaly do not survive infancy.

Can anencephaly be treated?
No cure, but supportive care may be provided.

What is the prognosis for babies with anencephaly?
Generally poor, with most dying shortly after birth.

How common is anencephaly?
Affects about 1 in 4,600 births.

Article last updated on: 25th June 2025.
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