OBJECTIVES: Arterial embolization of myomas (AEM) is controversial because of the changes that occur in the extracellular matrix (ECM) of the endometrium and its effect on gestational success in infertile patients desiring reproductive capability. Therefore, we performed this study on the expression of genes in the ECM of the endometrium, such as those coding metalloproteinases (MMP), before and 6 months after embolization of the uterine arteries. METHODS: Seven women with leiomyomas were evaluated, and MMP3 and MMP10 levels were measured. The women underwent pelvic nuclear magnetic resonance (NMR), examination, and endometrial biopsy between the 20 th and 24 th day of the menstrual cycle, and pre- and post-AEM (after 6 months). For data analysis, the Cq comparative method, also known as the 2-ΔΔCT method, was used to calculate the relative quantities of MMP gene expression among the samples collected. RESULTS: There was a significant decrease by 9.52 times in the expression of MMP3 ( p =0.007), and a non-significant change in the expression of MMP10 ( p =0.22) in post-AEM-treated women than pre-AEM-treated women. CONCLUSIONS: The results suggest that ECM continues to undergo tissue remodeling 6 months after AEM, at least with regard to MMP3 expression, suggesting that AEM affects the ECM for at least 6 months after the procedure.