Effects of gonadotropin-releasing hormone and raloxifene on the size of uterine leiomyoma

BACKGROUND: Uterine leiomyoma is a prevalent benign tumor. Several studies have proved the positive effects of raloxifene in the treatment of leiomyomas. Since raloxifene has fewer side effects than the gonadotropin-releasing hormone (GnRH) agonist, if proven effective, it can be applied easily. This study aimed to compare the medical effects of raloxifene and GnRH on uterine leiomyoma size. METHODS: This study was a clinical trial which involved 53 women with uterine leiomyoma. Participants were randomly divided into 2 groups of raloxifene and GnRH. The GnRH group received 1 dose per month (intramuscular injection) and the raloxifene group received a daily dose of raloxifene 60 mg/orally for 3 months. The size of the leiomyoma, prior and during the intervention, was determined by a sonographer. During the study, repeated measurement was used for comparing trend in the logarithm of tumor size. RESULTS: Analysis of changes in leiomyoma tumor size (log of tumor size) by repeated measurement showed that decrease in tumor size in the raloxifene group was significantly higher than GnRH group (P = 0.042). The trends of changes in endometrial thickness were different in the 2 groups and the reduction of thickness was more significant in the GnRH group (P = 0.026). CONCLUSION: Overall, this study showed that raloxifene is an appropriate medicine to reduce the size of uterine leiomyoma and it is more effective than GnRH.