Objectives: To compare the efficacy, safety and other clinical benefits of the levonorgestrel-releasing intrauterine system (LNG-IUS) and gonadotropin-releasing hormone analogues (GnRH-a) in women with endometriosis.
Methods: A systematic search was carried out using the Cochrane Central Register of Controlled Trials, PubMed, MEDLINE™ and EMBASE databases for all randomized controlled trials (RCTs) that evaluated the use of the LNG-IUS and GnRH-a in premenopausal women with endometriosis.
Results: Five RCTs studies were identified. A meta-analysis showed that, in women with endometriosis, both the LNG-IUS and GnRH-a reduced pain visual analogue scale scores (weighted mean difference [WMD] 0.03 [95% confidence interval [CI] -0.53, 0.59]), serum levels of CA125 (WMD -12.29 [95% CI -29.90, 3.32]), and American Society of Reproductive Medicine staging scores (WMD 1.10 [95% CI -27.98, 30.18]). Psychological and general wellbeing index scores were increased (WMD 1.50 [95% CI -6.19, 9.19]). Levels of low-density lipoprotein cholesterol were also significantly reduced in patients treated with the LNG-IUS (WMD 39.30 [95% CI 6.74, 71.86]).
Conclusions: The LNG-IUS had clinical efficacy equivalent to that of GnRH-a but may have some clinical advantages over GnRH-a in the treatment of endometriosis-associated symptoms. These observations will require further verification in additional studies employing larger patient populations.
Keywords: Endometriosis; gonadotropin-releasing hormone analogue; levonorgestrel-releasing intrauterine system; meta-analysis.