1. Trisomy 21 (Down syndrome)
    This is caused by an extra copy of chromosome 21 and is also called Down syndrome. This is the most common genetic cause of intellectual disability. Individuals with Down syndrome have some degree of intellectual disability (average IQ of 50). Some children with Down syndrome have congenital defects of the heart or other organs that may require surgery or medical treatment. Some have other medical conditions including hearing or vision loss, and at a later age dementia.
  2. Trisomy 18 (Edwards syndrome)
    This is caused by an extra copy of chromosome 18 and is also called Edwards syndrome. Most babies with trisomy 18 have multiple severe birth defects of the brain, heart and other organs. Poor growth during pregnancy is common and many babies are miscarried or stillborn. Of those babies born alive, most die before one year of age. Babies who survive have profound intellectual disabilities and growth and developmental problems.
  3. Trisomy 13 (Patau syndrome)
    This is caused by an extra copy of chromosome 13 and is also called Patau syndrome. Most babies with trisomy 13 have multiple severe birth defects of the brain and other organs. Many babies are miscarried or stillborn. Of those babies born alive, most die before one year of age.
  4. The sex of the baby is determined and is reported upon request
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