Department of Obstetrics and Gynecology and Maternity BB Stockholm, Danderyd Hospital, the Department of Clinical Sciences, Danderyd Hospital, the Department of Medicine, Center for Pharmacoepidemiology, and the Department of Women's and Children's Health, Karolinska Institute, and Karolinska University Hospital, Stockholm, and the School of Health and Welfare, Dalarna University, Falun, Sweden.
Obstet Gynecol. 2022 Aug 1;140(2):227-233. doi: 10.1097/AOG.0000000000004846. Epub 2022 Jul 6.
To assess the Pearl Index for risk of ectopic pregnancy in women using levonorgestrel-releasing intrauterine systems (LNG-IUS) with hormonal reservoirs of 13.5 mg, 19.5 mg, or 52 mg.
This was a retrospective cohort study. Women diagnosed with an ectopic pregnancy in Stockholm County, Sweden, between January 1, 2014, and December 31, 2019, were identified through the electronic medical record system. The final analysis included 2,252 cases of ectopic pregnancy. Information on age, reproductive and medical history, as well as current use of contraception was retrieved. The time of intrauterine device (IUD) insertion before ectopic pregnancy and the numbers of sold LNG-IUS during the study period were used to calculate the incidence rate for ectopic pregnancy during use per 100 woman-years (Pearl Index).
Among women with an ectopic pregnancy diagnosis, 105 presented with a known type of hormonal IUD in situ, of whom 94 were included in the calculations of the Pearl Index. The estimated Pearl Index for ectopic pregnancy was 0.136 (95% CI 0.106-0.176) for the LNG-IUS 13.5-mg, 0.037 (95% CI 0.021-0.067) for the LNG-IUS 19.5-mg, and 0.009 (95% CI 0.006-0.014) for the LNG-IUS 52-mg. With the 52-mg LNG-IUS as referent, the relative risk (RR) for ectopic pregnancy was higher during the first year for LNG 13.5-mg (RR 20.59, 95% CI 12.04-35.21), and for both 13.5-mg (RR 14.49, 95% CI 9.01-23.3) and 19.5-mg (RR 4.44, 95% CI 1.64-12.00) during the total study period.
The absolute risk of ectopic pregnancy during the use of LNG-IUS at any doses was low. The results show that the lower the dose of the IUD, the higher the risk of an ectopic pregnancy. Higher-dose LNG-IUS should be considered when providing contraceptive counseling to a woman with known risk factors for ectopic pregnancy who are considering a hormonal IUD.
评估使用含 13.5 毫克、19.5 毫克或 52 毫克激素储库的左炔诺孕酮释放宫内节育系统（LNG-IUS）的妇女异位妊娠的 Pearl 指数。
这是一项回顾性队列研究。通过电子病历系统，在瑞典斯德哥尔摩县确定了 2014 年 1 月 1 日至 2019 年 12 月 31 日期间诊断为异位妊娠的妇女。最终分析包括 2252 例异位妊娠病例。检索了年龄、生殖和病史以及当前避孕措施的信息。根据异位妊娠前宫内节育器（IUD）插入的时间和研究期间销售的 LNG-IUS 数量，计算每 100 名女性年异位妊娠的发生率（Pearl 指数）。
在诊断为异位妊娠的妇女中，有 105 名妇女 IUD 为已知类型的激素 IUD，其中 94 名妇女纳入 Pearl 指数计算。LNG-IUS 13.5 毫克的估计异位妊娠 Pearl 指数为 0.136（95%CI 0.106-0.176），LNG-IUS 19.5 毫克为 0.037（95%CI 0.021-0.067），LNG-IUS 52 毫克为 0.009（95%CI 0.006-0.014）。以 52 毫克 LNG-IUS 为参照，LNG 13.5 毫克的异位妊娠风险在第一年较高（RR 20.59，95%CI 12.04-35.21），LNG 13.5 毫克（RR 14.49，95%CI 9.01-23.3）和 LNG 19.5 毫克（RR 4.44，95%CI 1.64-12.00）在整个研究期间的风险均较高。
任何剂量的 LNG-IUS 使用期间异位妊娠的绝对风险均较低。结果表明，IUD 剂量越低，异位妊娠的风险越高。对于已知异位妊娠风险因素并考虑使用激素 IUD 的女性，在提供避孕咨询时应考虑使用较高剂量的 LNG-IUS。
