Down’s syndrome screening is currently free in most parts of the country and can be performed at your local maternal and child health center. It is a safe, non-invasive screening test that is often used to check for trisomy 21, trisomy 18, trisomy 13 and other disorders. Although the screening test is non-invasive, the accuracy rate is relatively low, and even if a low-risk patient is detected, it does not mean that it is absolutely safe.