Prenatal Cytogenetics Diagnosis And Karyotype Analysis Of2619Cases Of Older Pregnant Women

Object:This paper makes a chromosome karyotype analysis of the amniotic fluid in2619cases of elder pregnant women, and probes into the probabilities and main types of the chromosome anomaly of their embryos. It also proves genetic consultancies and prenatal diagnosis to be necessary.Methods:This research collected the data from2619elderly pregnant women patients (aged at and over35years) in the Department of Obstetrics and the Department of Genetic Consultancy in the Women’s Hospital attached to the School of Medicine of Zhejiang University. It empirically analyses the chromosomal karyotype of Amniotic puncture, and makes an account of the puncture success rate, the conlplication, the cell culture achievement and the chromosomal abnonnality. Result:Among the2619cases of amniocentesis, the achievement ratio of amniocentesis was99%(with26failures in all2619empirical studies). The probability of complications is counted to be1/1000; and all pregnancies are well secured except for one induced abortion selected by the patient. The probability of the chromosomal anomaly is5.54%with145cases tested to be abnormal. There are32cases of abnormal number’s autosomes (24cases of Down Syndrome),45cases of autosomal structural abnormalities,15cases of abnormal sex chromosome number,2cases of abnormal sex chromosome structure, and51cases of Chromosome polymorphism. This paper also argues that therere prominent differences of Down Syndrome between the women aged from35to40and those from41to46(0.55%and4.49%respectively, x2=38.01, P<0.05).Conclusion:The research paper argues that the chromosomal karyotyping analysis of the amniotic fluid is a safe, effective and applicable method of the prenatal testing of infectious diseases. Also it explores that amniocentesis can induce the least complications and difficulties, and best to be performed at the middle of the pregnancy (usually18-23weeks). Compared with the common peers, elderly pregnant women are more easily to be found with trisomy21, trisomy18, reciprocal translocation, robertsonian translocation, so that they are mostly suggested to perform the pre-natal testing of the chromosomal karyotype of the amniotic fluid. By doing so, the risks of deformities and dementias induced by the chromosomal anomaly can largely be controlled, and the applicability of genetic consultancies and prenatal diagnosis is well proved to be the best approach of securing a good birth.