Infertile couples undergoing Assisted Reproductive techniques are really receptive to any intervention intended to enhancement their fertility. Successful implantation of an embryo requires a receptive endometrium, a good quality embryo, and embryo endometrial synchronization in all species. Pharmacological agents such as aspirin and sildenafil have been included in previous clinical trials to improve endometrial vascularity and perifollicular blood flow but the results were inconsistent. To evaluate the effect of oral low dose aspirin or vaginal sildenafil citrate on endometrial thickness, retrieved oocyte, degree of maturation, embryo quality and pregnancy test. This comparative prospective study was conducted on the 60 infertile women who participated in intracytoplasmic sperm injection (ICSI) cycles at the infertility clinic associated with the "High Institute of Infertility Diagnosis and Assisted Reproductive Technologies, Al-Nahrain University / Baghdad/ Iraq." December 2020 to June 2022. In the present study the count of total oocytes retrieved was significantly higher in aspirin treated group in comparison to sildenafil treated group 12.5 ±5.3 versus 9.37 ±5.5 respectively. No significant variation in mean endometrial thickness among study groups. Regarding biochemical pregnancy test, positive results were obtained in 12 (40.0 %), 10 (33.3 %) in aspirin treated group, sildenafil treated group respectively and the difference was not significant. Aspirin treatment resulted in higher number of total retrieved oocytes, aspirin and sildenafil did not improve endometrial thickness, but they resulted in improvement of sub endometrial vascularity; however, biochemical pregnancy test was not affected by either pharmacological agent.