Checking embryos for chromosome deletions is generally done by non-invasive DNA, chorionic villus biopsy, amniocentesis, and cord blood puncture. Chromosome deletion refers to the loss of a segment on the chromosome of an organism, and the loss of genes located in this segment occurs after the deletion. It may be mainly related to genetic, chemical, physical and biological factors and needs to be analyzed on a case-by-case basis. 1. Non-invasive DNA: This is done by drawing peripheral blood from the mother, which contains fetal DNA, so as to be able to detect whether there is any problem with the chromosomes of the fetus. 2. chorionic villus biopsy: generally before the 12th week of pregnancy, the fetal chorionic villus is extracted by puncture, which is a test to directly determine whether there are any chromosomal problems in the fetus. 3. Amniocentesis: Amniocentesis is the most common way to determine whether there is any chromosome problem in the fetus during pregnancy. The fetal decidualized cells are extracted directly through amniocentesis, so that the chromosomes extracted from the decidualized cells directly represent the chromosomes of the fetus. 4. Umbilical cord blood puncture: Umbilical cord blood puncture is generally used in cases where the pregnancy week is relatively large and amniocentesis is no longer possible. The risk of umbilical cord blood puncture is relatively high, but due to the direct extraction of fetal blood from the umbilical cord, it is also able to carry out a diagnostic examination of fetal chromosomes. The consequences of chromosome deletion are more serious, and you should go to a regular hospital for a comprehensive examination and appropriate follow-up treatment.