自然流产是指妊娠不足28周,胎儿体重低于1 000 g终止妊娠者,其发病率占全部妊娠的10%~15%,多为早期流产。约50%的早期自然流产与胚胎染色体异常有关。细胞遗传学分析显示:86%的染色体异常是数量异常,包括三体、单体及多倍体(三倍体或四倍体);6%的染色体异常是结构异常(传统核型可检测到的重复和缺失);8%的染色体异 Spontaneous abortion refers to less than 28 weeks of pregnancy, fetal weight less than 1 000 g termination of pregnancy, the incidence of all pregnancies accounted for 10% to 15%, mostly for early abortion. Approximately 50% of early spontaneous abortions are associated with embryonic chromosomal abnormalities. Cytogenetic analysis showed that 86% of chromosomal abnormalities are anomalous in numbers, including trisomy, haploid and polyploid (triploid or tetraploid); 6% chromosomal abnormalities are structural abnormalities (traditional karyotypes are detectable Repeats and deletions); 8% of the chromosomes are different