Down’s anomaly means that the fetus is at a higher risk of having Down’s syndrome, that is, the results of the Down’s screening test suggest an abnormality. The Down’s syndrome test measures the concentrations of alpha fetoprotein, human chorionic gonadotropin, and free estriol in a pregnant woman’s blood and is used in conjunction with the woman’s age, weight, and number of weeks of gestation to determine the fetus’ risk of developing Down’s syndrome. Trisomy 21, also known as Down syndrome, is a congenital form of stupidity caused by chromosomal abnormalities. About 60% of children will be aborted in the fetus, and those who survive will have significant mental retardation, facial abnormalities, growth disorders, etc. If Down’s is abnormal, further prenatal diagnosis should be done to clarify whether the fetus is abnormal or not.