The aim of the study was to assess the effects of UPA on fibroid tissue, especially on the expression of estrogen and progesterone receptors, proliferative antigens and apoptosis index as well as the amount of tissue fibrosis, and to compare all of the above parameters in untreated, UPA treatment-responsive (significant volume reduction) and little to non-responsive leiomyomas. The gene discussed is PGR; the disease is leiomyoma.