Objective. To study the associations of polymorphic variants in the progesterone and estrogen receptor genes with the development of isolated uterine fibroids. Subjects and methods. Examinations were made in 977 females: 188 women with isolated uterine fibroids in the study group and 789 women in the control one. Five polymorphic loci of the estrogen and progesterone receptor genes: РGR c.1415-11113G> Т rs1042838, РGR c.*38Т> С rs484389, ESR1 c.*1029Т> С rs3798577, ESR1 c.453-397Т>С rs2234693, and ESR1 c. 453-351A>G rs9340799 were selected for the investigation. The latter was conducted using polymerase chain reaction on a CFX-96 Real-Time System thermal cycler. Results. There were associations of the polymorphic loci of РGR c.1415-11113G> Т rs1042838, ESR1 c.*1029Т> С rs3798577, ESR1 c.453-397Т> С rs2234693, and ESR1 c.453-351А> G rs9340799 with the formation of uterine fibroids. The risk factor for the development of isolated uterine fibroids is the A allele of ESR1 rs9340799 (OR = 1.35; p = 0.006). The higher genetic risk factors for uterine fibroids are a combination of the T allele of ESR1 rs3798577, the T allele of ESR1 rs2234693, and the A allele of ESR1 rs9340799 (OR = 1.60; p = 0.003). The combination of the G alleles of РGR rs1042838, the С allele of ESR1 rs2234693, and the G allele of ESR1 rs9340799 (OR = 0.64; p = 0.008) is of protecting value for developing uterine fibroids. Conclusion. The polymorphic loci of the genes PGR c.1415-11113G> Т rs1042838, ESR1 c.*1029Т> С rs3798577, ESR1 c.453-397Т> С rs2234693, and ESR1 c.453-351А> G rs9340799 are associated with the development of isolated uterine fibroids. © 2020, Bionika Media Ltd.. All rights reserved.