目的　了解米非司酮终止早孕失败者是否存在孕激素受体基因第 8外显子的突变。方法　 2 0 0 0年3～ 1 2月 ,以 1 7例药物流产后继续妊娠者为研究对象 ,随机选择 2 5例药物流产成功的妇女为对照组 ,收集其蜕膜组织和外周血 ,提取DNA ,进行聚合酶链反应 (PCR)和PCR产物测序。结果　对照组孕激素受体基因第 8外显子无突变存在 ,继续妊娠者中 8例在相当于第 86 6遗传密码子处见一同义突变位点 (CAA→CAG)。结论　米非司酮终止早孕失败者孕激素受体基因第 8外显子存在一同义突变位点 Objective To investigate whether mutations in exon 8 of the progesterone receptor gene are present in patients who fail the early pregnancy of mifepristone. Methods From March to February 2002, 17 consecutive pregnant women after medical abortion were enrolled. Twenty-five women who succeeded in medical abortion were randomly selected as the control group, their decidual tissue and peripheral blood were collected and extracted DNA, polymerase chain reaction (PCR) and PCR product sequencing. Results There was no mutation in the exon 8 of the progesterone receptor gene in the control group, and 8 cases of continuing pregnancy showed a synonymous mutation site (CAA → CAG) at the equivalent of the 866th genetic code. Conclusions There is a synonymous mutation site in the exon 8 of progesterone receptor gene in mifepristone patients with termination of early pregnancy failure