Noninvasive prenatal genetic testing technique is a safe, accurate, rapid and simple model of fetal chromosomal disease detection technology, collecting venous blood of pregnant women, free DNA was extracted from, non euploid fetal judgment on whether women harbored chromosomes using high-throughput sequencing technology. The prenatal diagnosis technology system, to reduce neonatal birth defect rate, eugenics has significant is that the technology has both is much higher than that of prenatal screening, close to the accuracy of prenatal diagnosis, and has the advantage of avoiding the characteristics of fetal intrauterine infection and abortion in pregnant women, and in 12 weeks of pregnancy can be tested.
From the beginning of the 4 week of gestation, fetal free DNA can be detected in the blood of pregnant women. With the increase of gestational age, fetal free DNA content also increased. After 12 weeks of pregnancy, pregnant women were collected by the peripheral blood (5ml) and from extract free fetal DNA, using the next generation sequencing technology combined with bioinformatics analysis means, can be accurately judged whether the fetus with chromosome disease (trisomy 21, trisomy 18, trisomy 13). The best detection time of the method is in the early and middle stage of pregnancy. It has the characteristics of non invasive sampling, no abortion risk, high sensitivity and high accuracy.