Cytogenetical analysis of 1320 couples with histories of abnormal pregnancy

Objective To explore the relationship between the histories of abnormal pregnancy and chromosomal abnormality by using karyotype analysis technology in order to provide genetic consultation for secondary pregnancy.Methods The venousblood samples of 1 320 couples with the histories of abnormal pregnancy were obtained,and then the lymphocytes were cultured,metaphase were gained,karyotypes were analyzed under microscope after Giemsa staining.Results Among 2 640 cases(1 320 couples),there were 107 cases were found with abnormal karyotype,the abnormal rate was 4.05%.There were 8 cases were found with numerical abnormality of chromosomes,the abnormal rate was 0.30%;99 cases were found with structural abnormality of chromosomes,the abnormal rate was 3.75%,including 42 cases with balanced translocation,18 cases with robertsonian translocation,20 cases with chromosomal polymorphism,27 cases with inversion.There were 906 couples(1 812 cases) came to hospital because of abortion,the rate was 68.6%.There was no significant difference in the abnormal rate of chromosomal karyotype in different times of abortion and different genders(P 0.05).Conclusion Chromosomal abnormality is an important reason to lead to some diseases such as abortion,stillbirth and fetal malformation and so on,the couples with adverse pregnancy outcome should both receive genetic consultation and have prenatal diagnosis,the couples with chromosomal abnormality who get secondary pregnancy should have prenatal diagnosis to reduce the birth rate of infants with chromosomal abnormality.