Pregnancy is an important period in women life regarding different aspects including physical activity which may be effective on various health indices of offspring. One of the common and expanding women diseases is breast cancer and two of its related indices are BRCA1 and P53. Thus, the aim of present study was estimating the effect of aerobic training during pregnancy in pregnant rats on the expression of BRCA1 and P53 genes of their offspring’s breast tissue. 20 female Sprague Dawley rats were randomly divided into two groups of exercise during pregnancy (T) (221±9.9) and control (C) (223.8±12.8). The aerobic exercise training was performed immediately after observation of the vaginal plaque of approving pregnancy for
21 days and 5 sessions per week with moderate intensity. About 2 to 3 days before delivery, their training program was terminated. Tissue sampling of Pairs 4, 5, and 6 of breast tissues in
8 weeks offspring rats was performed to evaluate the expression of BRCA1 and P53 gene. Data was analyzed using SPSS software and statistical tests of Shapiro-Wilk to control the distribution of data, and independent t-test for comparisons of between groups. Aerobic training with moderate intensity during pregnancy increased significantly mRNA of the BRCA1 gene (P=0.001), but there was no significant change in mRNA of the P53 (P=0.69). Considering the effect of exercise during pregnancy on increasing BRCA1 gene expression in their offspring's and association of the gene with breast, it seems that moderate exercise during pregnancy can reduce the risk of breast cancer in children