通过绒毛活体取样,进行孕早期产前诊断已成为遗传疾病预防的一个新的方向。 绒毛滋养层细胞是受精卵有丝分裂的衍生物,它准确地反映了胎儿的遗传特性。妊娠早期的绒毛有较高的有丝分裂活性,这些特点为用直接法制备胎儿染色体、在孕早期检出染色体异常胎儿提供了有利条件, Through in vivo sampling of villus for prenatal diagnosis of early pregnancy has become a new direction of genetic disease prevention. Villus trophoblast cells are mitotic derivatives of fertilized eggs, which accurately reflect the genetic characteristics of the fetus. The early trimester villi have higher mitotic activity, these characteristics for the direct method of preparation of fetal chromosomes, early detection of fetal chromosomal abnormalities provided favorable conditions,