米索前列醇促宫颈成熟的效果及安全性评价

Safety and Efficacy of Intravaginal Misoprostol for Cervical Ripening in the Third Trimester of Pregnancy

目的：评价米索前列醇用于晚期妊娠促宫颈成熟的有效性及安全性。方法：采用随机双盲临床对照试验。宫颈Ｂｉｓｈｏｐ评分＜７分、有引产指征的单胎、头位妊娠８５例，分为试验组４３例（阴道给米索前列醇１００μｇ），对照组４２例（给予安慰剂）。用药前及用药１２小时后进行宫颈Ｂｉｓｈｏｐ评分，胎心电子监护，脐动脉、胎儿大脑中动脉和肾动脉收缩期最大血流速度（Ｓ）与舒张末期血流速度（Ｄ）的比值（Ｓ／Ｄ值）测定。如１２小时不临产，按常规行催产素引产。产后留取胎盘及蜕膜组织进行组织学观察。结果：用药１２小时后，试验组宫颈Ｂｉｓｈｏｐ评分升高平均为４．４±２．２分，明显高于对照组的１．０±０．９分。试验组用药后１２小时内自然临产发生率为６７．４％（２９／４３），显著高于对照组的１４．３％（６／４２）。两组用药前后脐动脉、大脑中动脉及肾动脉Ｓ／Ｄ值差异均无显著性（Ｐ＞０．０５）。两组胎心率监护异常发生率、胎儿窘迫发生率及新生儿Ａｐｇａｒ评分差异均无显著性。组织学观察除绒毛干及绒毛内血管呈不同程度扩张外，试验组胎盘及蜕膜组织学改变与对照组无其它不同。结论：米索前列醇（１００μｇ）用于晚期妊娠促宫颈成熟，安全、有效、用药方便。

Objective: To evaluate the safety and efficacy of intravaginal misoprostol for cervical ripening in late trimester. Method: A randomized, double blind, placebo controlled trial was conducted. 85 patients with indication for induction of labor and unfavorable cervices were randomly assigned to receive either intravaginal misoprostol (100 μg) or placebo placed in the posterior vaginal fornix at one time. The Bishop score, fetal heart rate monitoring and Doppler blood flow velocity waveforms were measured before and 12 hours after drug insertion. Placenta and decidua were observed histopathologically in some cases. Among 85 patients enrolled, 43 received misoprostol and 42 received placebo. Results: The mean initial Bishop scores were not significantly different between the two groups, while the mean Bishop score in the misoprostol group was significantly higher than that in the placebo group (4.4 for misoprostol versus 1.0 for placebo, P <0.01). The prevalence of spontaneous labor within 12 hours after misoprostol insertion (67.4%, 29/43) was significantly higher than that in the placebo group (14.3%, 6/42) ( P <0.01). The average Doppler velocity systolic to diastolic (S/D) ratios of umbilical artery, middle cerebral artery, renal artery were not significantly different before and 12 hours after drug insertion between both groups. There was no significant difference in frequency of abnormal fetal heart rate tracings or fetal distress and in the mean Apgar score between the two groups. Except the presence of vasodilation in villi vessels in the misoprostol group, no significant difference existed between the two groups in the placental and decidual histopathological changes. Conclusions: Intravaginal misoprostol may be an effective and safe cervical ripening agent in late pregnancy.