Merki-Feld Gabriele S, Schwarz Danielle, Imthurn B, Keller P J
Clinic of Endocrinology, Department of Gynecology and Obstetrics, University Hospital, Frauenklinikstr. 10, CH-8091 Zurich, Switzerland.
Eur J Obstet Gynecol Reprod Biol. 2008 Mar;137(1):92-6. doi: 10.1016/j.ejogrb.2007.02.003. Epub 2007 Mar 13.
The contraceptive efficacy of intrauterine devices (IUD) is thought to relate to the position of the IUD in the uterine cavity. Several trials examined the number of copper IUD expulsions, but none evaluated the partial and complete expulsion rate of the levonorgestrel-releasing device (LNG-IUD).
This retrospective cohort study compares the dislocation rate of the Multiload 375 IUD (ML 375) and the LNG-IUD in 214 women (107 subjects with each IUD). Transvaginal ultrasound was used to monitor the IUD position immediately after insertion, after 6 weeks, and later on at intervals of 6 months. The observation period included 3631 cycles.
We detected a significantly lower number of dislocations in LNG-IUD users. Previous expulsion was associated with a significantly higher risk for a re-expulsion in both IUD groups. Hypermenorrhea was not associated with an increased dislocation rate in LNG-IUD users.
Expulsions are less likely to occur with the LNG-IUD, which might contribute to its contraceptive efficacy.
宫内节育器（IUD）的避孕效果被认为与IUD在宫腔内的位置有关。多项试验研究了铜质IUD的排出情况，但尚无研究评估左炔诺孕酮宫内缓释系统（LNG-IUD）的部分和完全排出率。
这项回顾性队列研究比较了214名女性（每组107名受试者）使用的多负载375 IUD（ML 375）和LNG-IUD的移位率。在放置IUD后、6周后以及随后每6个月使用经阴道超声监测IUD位置。观察期包括3631个周期。
我们发现LNG-IUD使用者的移位次数明显较少。在两个IUD组中，既往排出与再次排出的风险显著更高相关。月经过多与LNG-IUD使用者移位率增加无关。
LNG-IUD发生排出的可能性较小，这可能有助于其避孕效果。
