Analysis of fetal chromosomal karyotypes in 300 pregnant women during the first trimester of gestation.

Objective:To analyze the fetal chromosomal karyotypes in prenatal diagnosis in order to avoid bearing fetus with hereditary disease.Methods: Fetal chromosomal karyotypes were examiner in 300 pregnant women(6 to 9 weeks, gestation) by smear.Results:18 abnormal chromosomal karyotypes were detected,the abnormal rate was 6.00%.Trisomy was the major abnormality,it was 10 out of 18(55.56%),including 7 trisomy 21,2 trisomy 18,1 trisomy 13,Balanced translocation was found in 7 fetuses,the freguency was 38.89%;Deletion was found in 1 fetus in 52 pregnant women aged over 35 years,3(5.77%) with trisomy 21 were detected,and 4 of trisomy 21 were in 248 pregnant women aged under 35 years(3.16%),χ2=1.6900 P=0.1931.Conclusion: Villi direct smear in early pregnancy is important methods of birthy health.