The notice will be given in a few days if there is a problem with the Down’s screening, usually in about seven days. Because Down’s syndrome is also known as trisomy 21, Down’s screening is a prenatal screening for Down’s syndrome to determine the risk of Down’s syndrome in the fetus in the womb. The best time to be screened for Down’s syndrome is between 15 and 20 weeks of gestation. There is no good treatment for children with Down’s syndrome. Children with Down’s syndrome are born with severe mental retardation and cannot take care of themselves at all.