Abstract Objective To investigate the effect of exogenous ovarian stimulation with human menopausal gonadotropin (hMG) and recombinant follicle stimulating hormone (rFSH) on the expression of integrins alpha(3), beta(1) in the rat endometrium during implantation. Study design Following three successive normal estrous cycles the animals were divided into five groups: Group I ( n = 10, control group) received no medication; Group II ( n = 10) received 10 units of hMG; Group III ( n = 10) received 20 units of hMG; Group IV ( n = 10) received 10 units of rFSH; Group V ( n = 10) received 20 units of rFSH at midday of middiestrous. The rats were then mated with fertile males. The animals were sacrificed on the day of implantation. The uterine horns were placed in fixative and paraffin blocks of the tissue were cut in 5 μm sections. The tissues were stained with primary antibodies; monoclonal anti-integrin alpha(3) and monoclonal anti-integrin beta(1) using immunohistochemical methods. The staining intensities of alpha(3) and beta(1) integrins were calculated separately for epithelium and stroma in each group. Results Staining intensities of alpha(3) and beta(1) integrins in both the epithelium and the stroma were significantly lower in the treatment groups than the control group ( p < 0.05). Conclusion Ovarian stimulation by low and high doses of HMG and rFSH may have an effect on endometrial receptivity, possibly via a decrease in expression of integrins in the endometrium during the implantation period.