Screening tests and diagnostic testing are the two types of tests available to detect Down syndrome during pregnancy. A screening test can notify a woman if the pregnancy has a reduced or higher risk of having Down syndrome. Although screening tests can not provide a definitive diagnosis, they are safer for both the mother and the developing foetus. Diagnostic tests can usually predict a definitive diagnosis if a newborn will have Down syndrome, but they are more dangerous for the mother and the fetus. None, not even screening or diagnostic testing, can foresee the full impact of Down syndrome on a baby.