Levonorgestrel-Releasing Intrauterine Systems Versus Oral Cyclic Medroxyprogesterone Acetate in Endometrial Hyperplasia Therapy: A Meta-Analysis

This study aimed to compare the levonorgestrel-releasing intrauterine system (LNG-IUS) with oral cyclic medroxyprogesterone acetate (MPA) in endometrial hyperplasia therapy using randomized controlled trials (RCTs). The study searched MEDLINE, EMBASE, CENTRAL, and other databases. All regression outcomes were calculated for dichotomous outcomes in terms of relative risk (RR) and 95% confidence intervals (CIs) using a Mantel-Haenszel random effects model. The search found 543 articles but selected 342 articles after the removal of duplicates. A meta-analysis found five RCTs (377 patients). The study did not analyze RR for total outcome because of high heterogeneity (I (2) = 87%). In a subgroup analysis of studies with non-obese women, the LNG-IUS treatment appeared to have a higher regression rate than oral MPA (RR 1.41; 95% CI 1.23-1.62; 4 trials, 265 patients; I (2) = 0%). In a subgroup analysis of studies with obese women, LNG-IUS appeared to have a regression rate similar to that of oral MPA (RR 1.03; 95% CI 0.94-1.13; 1 trial, 60 patients). In a subgroup analysis according to histology in the non-obese group, the LNG-IUS treatment appeared to have a higher regression rate than oral cyclic MPA in a meta-analysis of women with non-atypical endometrial hyperplasia (RR 1.36; 95% CI 1.07-1.73; 2 trials, 92 patients; I (2) = 6%) and mixed endometrial hyperplasia (atypical and non-atypical) (RR 1.44; 95% CI 1.21-1.71; 2 trials, 173 patients; I (2) = 0%). The LNG-IUS treatment has a higher regression rate than cyclic MPA in non-atypical endometrial hyperplasia and mixed endometrial hyperplasia therapy for non-obese women but has a similar regression rate, albeit limited, for obese women.