Down syndrome, Edwards syndrome and Patau syndrome are genetic disorders caused by chromosomal trisomies. Down syndrome is caused by an extra copy of chromosome 21 whereas Edwards syndrome and Patau syndrome are caused by an extra copy of chromosome 18 and chromosome 13, respectively. Down syndrome is characterized by intellectual impairment and congenital abnormalities. Down syndrome occurs approximately in 1 in 700 pregnancies but is more frequent in pregnancies in women over 35. Edwards syndrome and Patau syndrome are less common occurring in 1 in 3000 and 1 in 10000 pregnancies, respectively. Edwards and Patau syndromes are characterized by severe congenital abnormalities and rarely survive past the first year of life. Ask your doctor about using VERACITY to detect these fetal trisomies.