Generally pregnant women over 35 years of age are not likely to pass the Down screening. Down’s syndrome is a test that detects the risk of trisomy 21, trisomy 18 and open neural tube malformation in the fetus. It is done by taking the vein blood of a pregnant woman, testing the values of alpha-fetoprotein and human chorionic gonadotropin in the blood, and combining with the age and weight of the pregnant woman and the gestational week at the time of the blood collection, etc. to comprehensively determine the risk factor of having a Down’s syndrome baby. Pregnant women over the age of 35 are usually less likely to pass the Down’s syndrome test. This is because pregnant women over the age of 35 are at high risk for fetal chromosomal abnormalities and have a greater chance of developing Down’s syndrome. Pregnant women over the age of 35 are usually recommended to undergo non-invasive DNA screening or amniocentesis directly. Down screening is recommended to regular hospitals, any abnormalities need to be timely medical treatment, by the doctor to give a standardized program.