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?
Typically due to genetic or environmental factors during fetal development, possibly related to folic acid deficiency.

Is Anencephaly inherited?
Usually not, but may be associated with genetic mutations or family history in some cases.

Can Anencephaly be prevented?
Possibly, through folic acid supplementation before and during pregnancy, but not all cases can be prevented.

How common is Anencephaly?
Affects about 1 in 4,600 births in the United States, with varying rates worldwide.

What are the symptoms of Anencephaly?
Typically, absence of a large portion of the brain and skull, leading to severe physical deformities.

Can babies with Anencephaly survive?
Usually not, as most die within days or weeks after birth due to associated complications.

Is there a cure for Anencephaly?
No known cure, but supportive care can be provided to affected infants and their families.

How is Anencephaly diagnosed?
Through prenatal ultrasound and other imaging tests during pregnancy, often confirmed after birth.

What are the risks for future pregnancies if a couple has a child with Anencephaly?
Possibly increased risk of recurrence, depending on underlying genetic or environmental factors.

Article last updated on: 18th October 2025.
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