All pregnant women should be offered screening for Down syndrome in their first trimester, according to new practice guidelines to be issued by the American College of Obstetricians and Gynecologists. This is applicable to younger pregnant women regardless of their age.
Down syndrome or trisomy 21 (also Down’s syndrome) is a genetic disorder caused by the presence of all or part of an extra 21st chromosome. It is named after John Langdon Down, the British doctor who first described it in 1866.
The Down Syndrome condition is characterized by a combination of major and minor differences in body structure. Often Down syndrome is associated with some impairment of cognitive ability and physical growth as well as facial appearance. Down syndrome is usually identified at birth.
Noninvasive screening tests made it possible to predict the risk of Down syndrome and certain other chromosomal abnormalities with high accuracy. Pregnancies identified as being at risk then can be offered further screening with invasive, and more dangerous, tests such as amniocentesis or chorionic villus sampling, according to the guidelines published in the January issue of the journal Obstetrics & Gynecology.