Down screening is also known as Down’s syndrome screening, 28 years old pregnant Down’s syndrome screening is generally easier to pass, but it is not absolute, the specific situation should be judged according to the individual. Between 16 and 20 weeks of pregnancy, a woman can go to the hospital and have her peripheral blood drawn for Down’s screening, which is a basic test that detects alpha-fetoprotein, free human chorionic gonadotropin HCG, and estriol in the blood, and combines with the age of the pregnant woman and the week of gestation, etc., to determine the probability of the fetus suffering from Down’s syndrome. The presence of chromosomal abnormalities in both spouses, family genetic history, abnormal pregnancies, advanced age of the woman, poor egg quality, etc., after pregnancy, the fetus is more likely to develop Down’s syndrome, and the Down’s syndrome screening test may have a critical risk or high-risk results, it will not be easy to pass. After pregnancy, it is recommended that every woman should do a good maternity test at all times of pregnancy, so that any abnormalities can be dealt with in time.