Symptoms and Signs of Trisomy 18 (Edwards Syndrome)

Medical Author:
Medically Reviewed on 9/14/2022

Doctor's Notes on Trisomy 18 (Edwards Syndrome)

Trisomy 18 (Edwards syndrome) is a severe genetic disorder where patients have an extra copy of chromosome 18. Trisomy 18 leads to severe intellectual disability and abnormalities in many organs. The prognosis of trisomy 18 is poor. Half of those affected do not live beyond the first week of life and a low percentage of infants with this condition live beyond the first year.
Common symptoms of trisomy 18 (Edwards syndrome) include

  • birth defects such as low birth weight,
  • small jaw and mouth;
  • abnormally shaped, small head;
  • overlapping fingers and clenched fists;
  • “rocker-bottom” feet,
  • low-set ears, and
  • defects in the heart and other organs.

Symptoms of trisomy 18 in infants who survive include

  • poor feeding,
  • respiratory problems,
  • delayed growth,
  • mental impairment, and
  • other life-threatening complications.

What is the treatment for trisomy 18?

Unfortunately, there are no treatments or cures for trisomy 18. Researchers do not know how to prevent the problem. At best, treatments are for symptoms such as heart problems, breathing, and infections. The prognosis is poor; only about 10% survive to age 1. Support for parents and others is available with organizations like the Trisomy 18 foundation.


Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education, 2015.