Down syndrome (DS for its acronym in English), also known as Trisomy 21, the condition in which extra genetic material causes delays in the way a child develops mentally and physically. This condition affects 1 in every 800 babies.
Prevalence at Birth
The birth prevalence is measured by considering the relationship between the cases of Down syndrome (live births) and total live births. Please note that a significant percentage of cases of Down syndrome are identified through prenatal diagnosis and consequently affected pregnancies are not completed. (kidshealth.org 2011)
The data is taken from hospital discharge records (HDR) which are mandatory ...