Children with intellectual disability may take longer to learn to speak, walk, and take care of their personal needs such as dressing or eating. They are likely to have trouble learning in school. They will learn, but it will take them longer. There may be some things they cannot learn.

What Causes an Intellectual Disability?

Doctors have found many causes of intellectual disability. The most common are:

• Genetic Conditions
  Sometimes intellectual disability is caused by abnormal genes inherited from parents, errors when genes combine, or other reasons. Examples of genetic conditions are Down syndrome, fragile X syndrome, and phenylketonuria (PKU).
• Problems During Pregnancy
  Intellectual disability can result when a baby does not develop usually during gestation. For example, there may be a problem with the way the baby's cells divide as it grows. A woman who drinks alcohol or gets an infection like rubella during pregnancy may also have a baby with an intellectual disability.
• Problems at Birth
  If a baby has problems during labor and birth, such as not getting enough oxygen, he or she may have an intellectual disability.
• Health Problems
  Diseases like whooping cough, the measles, or meningitis can cause an intellectual disability. Intellectual disabilities can also be caused by extreme malnutrition (not eating right), not getting enough medical care, or exposure to poisons like lead or mercury.

Intellectual disability is not a disease. You can not catch it from anyone. Intellectual disability is also not a type of mental illness, like depression. There is no cure for intellectual disability. However, most children and adults with an intellectual disability can learn to do many things. It just takes them more time and effort than other people.