早孕期经腹绒毛活检及细胞遗传学分析在染色体疾病产前诊断中的应用

Application of trans-abdominal chorionic villus sampling and cytogenetic analysis in the prenatal diagnosis of chromosomal diseases in first trimester of gestation

目的：研究早孕期B超引导下经腹绒毛取材以及绒毛细胞长期培养和染色体制备方法，评价早孕期细胞遗传学分析在产前诊断中的应用价值。方法：回顾分析2001年1月到2005年12月77例早孕期产前细胞遗传学诊断的病例资料。结果：77例平均35．2岁，均为单胎妊娠。取材时间9～13周，平均10．69周，平均取材量为20．6rag，穿刺成功率100％，操作相关的自然流产率为1．3％，因取材不足无法进行产前诊断率为0，母体组织污染率为0。1例培养失败，培养成功率为98．7％，平均培养时间为5～7天，培养过程中细菌污染率为0。发现异常核型5例，限制性胎盘嵌舍体2例。因胎儿受累终止妊娠11例，已分娩正常新生儿27例，继续妊娠者34例。结论：孕9周后行B超引导下经腹绒毛取材是一项安全可行的早孕期介入性产前诊断方法。绒毛细胞长期培养法和染色体制备方法简单、技术稳定、结果可靠，可用于胎儿染色体疾病的产前诊断。

Objective ：To evaluate the feasibility and safety of prenatal diagnosis by transabdominal ehorionie villus sampling （TA-CVS） via the guidance of B-mode ultrasound in the first trimester of gestation. To research the method of long time culture and chromosome preparation of villi in early pregnancy. To evaluate the feasibility of the above method in the use of the prenatal eytogenetie diagnosis. Methods： Seventy-seven singleton pregnancies at risk were referred from January 2001 to December 2005. Results： The average maternal age was 35.2 years. TA-CVS was performed in the 9 - 13th weeks of gestation and the average gestational age was 10.69 weeks. The mean weight of the specimen was 20.6mg. All attempts at sampling were successful. The rate of operation-associated fetal loss was 1.30%. The failure rate of prenatal diagnosis because of inadequate amount of specimen was 0. The average culture time was 5 - 7 days. The success rate of the cell culture was 98.7%. No maternal contamination and bacterial contamination happened. Five eases of abnormal karyotype and two eases of confined placental mosaieism were found. Conclusions：TA-CVS appears safe and feasible and might to be offered in the prenatal diagnosis in the first trimester of gestation. The method of long time culture and chromosome preparation of villi is simple, stable and reliable. It is feasible to use these methods in the prenatal cytogenetic diagnose.