两种侵入性产前诊断技术的评估及染色体核型分析

目的: 系统评估现有的侵入性产前诊断技术的安全性、有效性及其手术并发症的发生率,并对产前诊断指征及各种异常核型的临床意义进行探讨。方法: 回顾性总结分析2005年3月至2012年5月中南大学湘雅二医院产前诊断中心所进行的羊膜腔穿刺、脐静脉穿刺的病例并分析其手术指征、成功率、安全性和并发症等情况;对25例异常染色体核型进行分析。结果: 2005年3月至2012年5月共对669例孕妇进行了侵入性产前诊断,其中羊膜腔穿刺组598例,脐静脉穿刺组71例,与脐静脉穿刺组比较,羊膜腔穿刺组有更高的穿刺成功率(91.54% vs 100%, P<0.05),更低的流产率(1.41% vs 0.33%,P<0.05)、异常染色体发现率(11.27% vs 2.84%,P<0.05)及医疗费用(880元vs 800元,P<0.05)。羊膜腔穿刺术及脐静脉穿刺的产前诊断指征前3位均为唐筛高风险、高龄孕妇、超声检查异常。侵入性产前诊断共发现异常染色体25例,其中21-三体6例,性染色体数目异常4例,常染色体平衡易位7例,标记染色体1例,嵌合体7例。结论: 羊膜腔穿刺作为成熟的产前诊断取材技术其临床应用是安全有效的;脐静脉穿刺的手术并发症发生率远高于羊膜腔穿刺不应作为染色体异常产前诊断的常规手段。染色体核型分析不仅能及时发现胎儿染色体异常,而且能为孕妇是否继续妊娠提供科学依据,有利于降低出生缺陷的发生率。

Application and evaluation of invasive prenatal diagnostic techniques and analysis of chromosomal karyotype

Objective: To evaluate the safety, effectiveness and complications of serial invasive prenatal diagnostic techniques, and to investigate the prenatal diagnosis indication as well as to analyze the abnormal chromosomal karyotype.
Methods: We retrospectively studied all patients from March 2005 to May 2012 who received amniocentesis and cordocentesis in the prenatal diagnosis center of Second Xiangya Hospital. The indication of the procedure, successful rate and complications were evaluated, and 25 abnormal chromosome nuclear types were analyzed.
Results: A total of 669 patients received invasive prenatal diagnosis from March 2005 to May 2012 in Second Xiangya Hospital: 598 received amniocentesis and 71 cordocentesis carried out. Compared with the cordocentesis group, the amniocentesis group had higher achievement ratio (91.54% vs 100%, P<0.05), lower spontaneous abortion rate (1.41% vs 0.33%, P<0.05), fewer abnormal karyotypes (11.27% vs 2.84%, P<0.05) and lower expenditure (880 yuan vs 800 yuan, P<0.05). Positive screening, advanced maternal age, and ultrasonography abnormality were the top 3 indications of amniocentesis and cordocentesis. We found 25 abnormal karyotypes, including 6 cases of trisomy 21, 4 sex chromosomal abnormalities, 7 autosomal balanced translocations, 1 marker chromosome, and 7 mosaics.
Conclusion: As a widely used invasive prenatal diagnosis, amniocentesis is safe and effective. The complications of cordocentesis are much higher than those of amniocentesis, which is not a proper routine procedure for prenatal diagnosis of abnormal karyotype. The analysis of karyotype not only can identify fetal chromosome abnormality, but also provide the scientific basis for pregnancy continuation, thus reducing the ratio of birth defect.