米索前列醇（下称米索）用于晚期妊娠引产，效果肯定，成功率高。为探索合理的给药剂量，我们应用3种不同的剂量应用于临床，分析如下。1资料与方法1997年7月～1998年6月间，选择我科住院单胎头位初产妇210例，无阴道分娩禁忌症及使用前列腺素禁忌症，孕周在37～42’Wb之间，将 Misoprostol (hereinafter referred to as misoprostol) for late pregnancy induction of labor, the effect is positive, high success rate. In order to explore a reasonable dose, we apply three different doses of clinical application, the analysis is as follows. 1 Materials and Methods July 1997 ~ June 1998, select our hospital single mothers primipara 210 cases of vaginal delivery contraindications and prostaglandin contraindications, gestational age between 37 ~ 42’Wb ,will