What is Trisomy 18 (Edwards Syndrome)?

Trisomy 18, also known as Edwards syndrome, is a condition that causes intellectual disability and a wide range of birth defects. It occurs when there are three copies of chromosome 18 in the cells of the body instead of two. The symptoms seen in trisomy 18 are a result of this extra material impacting the growth and development of an affected individual.

Typical features of trisomy 18 include poor growth, feeding difficulties, breathing issues, and intellectual disability. Most affected individuals have a heart defect. Birth defects and abnormalities in other areas of the body, such as the brain, spinal cord, gastrointestinal tract, eyes, and ears are also common. Due to the severity of trisomy 18, most affected individuals do not survive beyond the first year of life.

How common is Trisomy 18 (Edwards Syndrome)?

Trisomy 18 occurs in about 1 in 6,000 live births.

How is Trisomy 18 (Edwards Syndrome) treated?

There is no cure for trisomy 18. Treatment for the condition is directed at managing the specific symptoms an individual has. Common interventions may include nutritional support, treatment of infections, and medications to manage heart failure. In some cases, surgery may be done to repair birth defects. Affected individuals are often followed by a multidisciplinary team that includes various medical professionals and social services. Some families may opt to pursue palliative care, which focuses on improving quality of life and may have limited medical intervention.

What is the prognosis for an individual with Trisomy 18 (Edwards Syndrome)?

Trisomy 18 is considered a life-limiting condition. Many affected pregnancies will end in miscarriage or stillbirth. Up to 25% of individuals born with trisomy 18 will survive past one year of age.

Other names for
Trisomy 18

  • Edwards syndrome


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