Prenatal testing for intellectual disability: misperceptions and reality with lessons from Down syndrome.

Down syndrome is the most common cause of intellectual disability. In the United States, it is recommended that prenatal testing for Down syndrome be offered to all women. Because of this policy and consequent public perception, having Down syndrome has become a disadvantage in the prenatal period. However, in the postnatal period, there may be some advantage in having Down syndrome. To help parents make informed decisions about screening and testing, it is crucial to reconcile divergent prenatal and postnatal perspectives. Advancements in genetic technologies will also impact the informed consent process and need to be considered.