Screening for fetal chromosomal abnormalities is an essential part of prenatal care, especially for the high-risk mother. The most common chromosomal abnormalities are Down syndrome (Trisomy 21), Edwards syndrome (Trisomy 18) and Patau syndrome (Trisomy 13).
Down Syndrome (Trisomy 21) is associated with mild to moderate intellectual disabilities and may also lead to digestive issues and congenital heart defects. It is estimated that Trisomy 21 occurs in one out of every 740 newborns.
Edwards Syndrome (Trisomy 18) is due to an extra copy of chromosome 18, which is associated with a high rate of miscarriage. Infants born with Trisomy 18 often have congenital heart defects as well as various other medical conditions, shortening their lifespan. It is estimated that Trisomy 18 occurs in approximately one out of every 5,000 newborns.
Patau Syndrome (Trisomy 13) is due to an extra copy of chromosome 13, which is associated with a high rate of miscarriage. Infants born with Trisomy 13 usually have severe congenital heart defects and other medical conditions, and survival beyond the first year is rare. It is estimated that Trisomy 13 occurs in approximately one out of every 16,000 newborns.