Down screening, or Down’s syndrome screening, is a prenatal screening program. For Down’s syndrome screening, you will need to prepare your maternity booklet, results of previous pregnancy tests, results of ultrasound and identification of both parents. For Down’s syndrome screening, you will need to bring your birth certificate and previous pregnancy tests, as well as proof of identity for both or one of your parents. The Down’s syndrome test is usually done at 15-20 weeks, and the results are usually reported 14-15 working days after the blood is drawn. Usually, before the Down’s syndrome screening, an obstetric ultrasound is also needed to measure whether the fetal biparietal diameter is consistent with the gestational week, so pregnant women also need to bring the results of the ultrasound examination when they have the Down’s syndrome screening. Pregnant women should pay attention to a light diet and avoid over-exertion before the Down’s syndrome screening.