SERPINA3 (α-1-antichymotrypsin, AACT, ACT) is produced by the liver and released into plasma in an anti-inflammatory response and plays a role as a modulator of extracellular matrix (ECM) by inhibiting serine proteases. Numerous studies proved an increased level of SERPINA3 in many types of cancer, which could be linked to SERPINA3's anti-apoptotic function. In the context of progressive ECM fibrosis during the development of uterine fibroids, which are one of the most common hypertrophic changes within the uterus, it is interesting to describe the level of SERPINA3 protein in this type of lesion and the surrounding tissues. We used immunohistochemical staining of the SERPINA3 protein and compared the intensity of the signal between the myoma tissue and the surrounding normal tissue. We showed a surprising reduction in the amount of the SERPINA3 protein within uterine fibroids compared to surrounding tissues. This observation sheds new light on the role of this protein in the formation of proliferative changes and suggests that understanding the mechanism of its action may become the basis for the development of new diagnostic and therapeutic tools.