For Patients/Families

Down syndrome
A syndrome of characteristic physical findings in children caused by an extra chromosome number 21. Another name for this condition is trisomy 21. Characteristic findings are a widely spaced first and second toes, a single palmar (simian) crease, short fingers, a fold of tissue (called epicanthal fold) across the inner aspect of the eye, eyes that slant upward, decreased muscle tone, a flattened back portion of the head and a protruding tongue. The only way to make the diagnosis with certainty is to perform a chromosomal analysis either before birth (chorionic villus sampling or amniocentesis) or after birth (blood or tissue chromosomal analysis). The range of outcomes for these children is quite broad and many function quite well although few have normal levels of cognitive development.

The risk of having a child with Down Syndrome increases with maternal age. The risk for otherwise healthy women is as follows:

Risk of Down Syndrome

Age

25 years 1 in 1300

30 years 1 in 900

35 years 1 in 350

40 years 1 in 100

45 years 1 in 25

49 years 1 in 12