Fetal amniotic fluid identification method is a special method to identify the prenatal fetus with or without genetic diseases, amniotic fluid is obtained through uterine puncture, and the diagnosis is obtained through the following kinds of testing means: 1, chromosome karyotype analysis, using chorionic villus, amniotic fluid or fetal blood cell culture to detect chromosome karyotype. 2, gene detection, using fetal DNA molecular hybridization, restriction endonuclease, polymerase chain reaction, sequencing technology, etc., to detect gene Sequence is abnormal or not, at present, based on the comparison of microchip technology, genomic hybridization technology is widely used in prenatal diagnosis, and the second generation sequencing technology has made great progress in the application of this field.3, gene product detection, using amniotic fluid, chorionic villus and fetal blood to detect specific proteins, enzymes and metabolites, used to determine certain metabolic disorders in the fetus.