目的　探讨无损伤性产前诊断胎儿RhD血型的方法。方法　西安交通大学第二医院 1999年 2月至2 0 0 1年 12月 ,以妊娠 14～ 4 0周的单胎孕妇为对象 ,其中RhD阴性孕妇 8例 ,RhD阳性孕妇 12例 ,利用PCR技术对孕妇血浆中游离胎儿DNA进行RhD基因第 10外显子的特异性扩增 ,扩增片段长度为 186bp ,另外以等位基因RhCE基因为内对照 ,扩增片段长度为 136bp。结果　能同时扩增出 186bp和 136bp两条带 ,判断所妊娠胎儿血型为RhD阳性 ;扩增出 136bp一条带 ,判断所妊娠胎儿血型为RhD阴性。 8例RhD阴性孕妇中 ,5例扩增出136bp一条特异性片段 ,3例同时扩增出 136bp和 186bp两条特异性片段 ;12例RhD阳性孕妇血浆标本 ,均同时扩增出 136bp和 186bp两条特异性片段 ,所有RhD PCR扩增结果均得到脐血血清学检测结果的证实。 结论　利用孕妇血浆中游离胎儿DNA对胎儿RhD血型进行诊断 ,是一种简便、快速、特异性较高的产前诊断方法 ,值得临床推广应用。 Objective To investigate the method of non-invasive prenatal diagnosis of fetal RhD blood type. Methods The second hospital of Xi’an Jiaotong University from February 1999 to December 2001 was targeted to singleton pregnant women who were between 14 and 40 weeks of pregnancy. Among them, 8 were RhD-negative pregnant women and 12 were RhD-positive pregnant women. PCR-based techniques RhD gene exon 10 was amplified specifically from fetal DNA in pregnant women. The length of amplified fragment was 186bp, and the allele RhCE gene was used as internal control. The length of amplified fragment was 136bp. Results The two bands of 186bp and 136bp could be amplified at the same time, and the blood type of the fetus was confirmed as RhD positive. A band of 136bp was amplified to determine that the blood type of the fetus was RhD negative. Of the 8 RhD-negative pregnant women, 136 bp and 136 bp were amplified in 5 out of the 3 cases, and two specific fragments of 136 bp and 186 bp were amplified in 3 cases. The plasma samples from 12 RhD positive pregnant women both amplified 136 bp and 186 bp Strip-specific fragments, all RhD PCR amplification results have been confirmed by cord blood serological test results. Conclusion It is a simple, rapid and specific prenatal diagnosis method to diagnose fetal RhD blood type by using fetal DNA in pregnant women ’s plasma, which is worthy of clinical application.