Trisomy 18 syndrome

Our Trisomy 18 Main Article provides a comprehensive look at the who, what, when and how of Trisomy 18

Medical Definition of Trisomy 18 syndrome

Trisomy 18 syndrome: The presence of three copies of chromosome 18, rather than the normal two. Children with trisomy 18 syndrome have multiple malformations and mental retardation. They characteristically have low birth weight, small head (microcephaly), small jaw (micrognathia), malformations of the heart and kidneys, clenched fists with abnormal finger positioning, and malformed feet. The mental retardation is profound, and the IQ is too low to even measure. Nineteen out of 20 children with trisomy 18 syndrome die before their first birthday. Also called Edwards syndrome.


Subscribe to MedicineNet's Children's Health & Parenting Newsletter

By clicking Submit, I agree to the MedicineNet's Terms & Conditions & Privacy Policy and understand that I may opt out of MedicineNet's subscriptions at any time.

Reviewed on 7/1/2016

Health Solutions From Our Sponsors