经阴道不同小剂量米索前列醇在孕晚期引产中的作用比较

Comparison of different low-dose of vaginal misoprostol for induction labor in late pregnancy

目的比较经阴道给予不同小剂量的米索前列醇在孕晚期引产的效果。方法选取晚期妊娠、有引产指征、宫颈Bishop评分≤6分的单胎孕妇共170例,随机分成米索前列醇12.5μg、25μg、50μg三组,且分别为58、56、56例。比较三组孕妇引产效果、分娩过程不良反应及新生儿结局。结果三组的引产效果和阴道分娩率无明显差异;给药至临产时50μg、25μg、12.5μg分别为（25.64±5.2小时、8.11±3.3小时、7.46±3.1小时）,12.5μg组时间明显长于25μg、50μg组（t值分别为132、111,均P〈0.01）;三组的从临产到胎儿娩出的时间分别为（8.53±3.5小时、6.55±2.9小时、6.02±2.8小时）,12.5μg组明显长于50μg、25μg组（t值分别为13.77、11,均P〈0.01）;12.5μg组需要加用缩宫素多于25μg和50μg组,但12.5μg和25μg组之间却无统计学意义。（χ^2值分别为0.676、5.996,P值分别是0.441、0.014）。宫缩过频、异常胎监50μg组显著高于25μg、12.5μg组。（χ^2值分别为6.127、4.553,P值分别为0.013、0.033）;新生儿不良结局三组间无显著差异。结论 50μg、25μg、12.5μg各小剂量米索前列醇在妊娠晚期引产均有很好效果,但12.5μg组引产时间长、50μg组的引产不良反应明显多,故经阴道每次25μg米索前列醇引产比较合适的选择。

Objective To compare the effect of different low-dose of vaginal misoprostol on induction of labor in late pregnancy. Methods Totally 170 late pregnant primiparous women with Bishop＇s score≤6 and singleton live pregnancy requiring labor induction were recruited.They were randomly assigned to three groups receiving 12. 5μg（ n = 58）,25μg（ n = 56） and 50μg（ n = 56） intravaginal misoprostol,respectively. Induction effectiveness,adverse reactions in labor and neonatal outcomes were compared among three groups. Results There were no significant differences among three groups in labor induction and rate of vaginal delivery. The mean interval between the first dose and active labor was significantly longer in 12. 5μg group（ 26. 25 ± 5. 2hrs） than in 25μg group（ 8. 11 ± 3. 3hrs） and 50μg group（ 7. 46 ± 3. 1hrs）（ t value was 132 and 111,respectively,both P〈0. 01）. The duration of in labor to expulsion in 12. 5μg group（ 8. 53 ± 3. 5h） was significantly longer than in 25μg group and 50μg group（ 6. 02 ± 2. 8h,6. 55 ± 2. 9h）（ t value was 13. 77 and 11,respectively,both P〈0. 01）. The need for oxytocin augmentation was higher in 12. 5μg group than in 25μg and 50μg group,but there was no statistical significance between 12. 5μg group and 25μg group（ χ^2value was 0. 676 and 5. 996,respectively,P value was 0. 441 and0. 014,respectively）. The incidence of hyperstimulation and abnormal fetal heart rate patterns was significantly higher in 50μg group than in other two groups（ χ^2value was 6. 127 and 4. 553,respectively,P value was 0. 013 and 0. 033,respectively）. However,there was no significant difference among these groups in adverse neonatal outcomes. Conclusion The low-dose of 50μg,25μg and 12. 5μg misoprostol has good effect on induced labor in late pregnancy,but the interval in 12. 5μg group is longer and the adverse reactions of 50μg group are remarkably more. Therefore,the dose of 25μg misoprostol is an appropriate choice for induction labor via vagina.