Misoprostol administration prior to intrauterine contraceptive device insertion: a systematic review and meta-analysis of randomised controlled trials

<b>Objectives:</b> Misoprostol has been used before intrauterine contraceptive device (IUCD) insertion to prime the cervical os. As the literature about this topic is controversial, we aimed to evaluate IUCD insertion failure, women’s pain perception, use of cervical dilators and prevalence of side effects following the administration of misoprostol. <b>Methods:</b> Trials published in MEDLINE, Scopus, the Cochrane Library and ClinicalTrials.gov were searched (last search on 23 October 2019). The primary outcome was IUCD insertion failure; secondary outcomes were women’s pain perception, use of cervical dilators to facilitate insertion, and prevalence of side effects. <b>Results:</b> Fourteen studies were eligible for inclusion. Misoprostol premedication reduced IUCD insertion failure rates and the use of cervical dilators but significantly increased the prevalence of side effects. The risk of IUCD insertion failure with misoprostol premedication was reduced among women who had undergone previous caesarean section and among women who had experienced previous IUCD insertion failure. Nulliparas did not benefit from misoprostol premedication. Buccal misoprostol administration did not seem to be effective in reducing IUCD insertion failure. Visual analogue scale pain scores were increased with both sublingual and buccal misoprostol administration if IUCD insertion was performed ≤2.5 h after misoprostol premedication. <b>Conclusion:</b> Our data demonstrate reduced IUCD insertion failure among women with previous caesarean section and those with previous IUCD insertion failure, suggesting that misoprostol may be a reasonable choice in these groups of women. Although misoprostol premedication reduced insertion failures, it significantly increased side effects and had a heterogeneous pattern of efficacy; thus, its routine use is not supported by the evidence.

<b>研究目的：</b> 米索前列醇（Misoprostol）曾被用于宫内节育器（Intrauterine Contraceptive Device, IUCD）放置术前，以完成宫颈口预处理。由于该领域相关研究结论尚存争议，本研究旨在评估米索前列醇给药后，IUCD放置失败率、受试者疼痛感知情况、宫颈扩张器（cervical dilators）使用情况及不良反应发生率。<b>研究方法：</b> 检索MEDLINE、Scopus、Cochrane图书馆及ClinicalTrials.gov数据库中收录的相关试验（末次检索时间为2019年10月23日）。本研究的主要结局指标为IUCD放置失败率；次要结局指标包括受试者疼痛感知、辅助放置所需的宫颈扩张器使用情况，以及不良反应发生率。<b>研究结果：</b> 最终纳入14项符合标准的研究。结果显示，米索前列醇预处理可降低IUCD放置失败率及宫颈扩张器使用需求，但显著升高不良反应发生率。既往有剖宫产史者、既往IUCD放置失败史者，使用米索前列醇预处理后IUCD放置失败风险进一步降低；而未产妇未从米索前列醇预处理中获益。颊黏膜给药途径未显示出降低IUCD放置失败率的效果。若在米索前列醇给药后≤2.5小时内实施IUCD放置，舌下给药与颊黏膜给药组的视觉模拟评分（Visual Analogue Scale, VAS）疼痛评分均有所升高。<b>结论：</b> 本研究数据表明，既往有剖宫产史及既往IUCD放置失败史的女性，使用米索前列醇预处理可显著降低放置失败率，提示该类人群可考虑选用米索前列醇。尽管米索前列醇预处理可减少IUCD放置失败事件，但会显著增加不良反应发生率，且疗效存在异质性，因此现有证据并不支持其常规临床应用。