Background: Ovarian hyperstimulation syndrome is the most serious iatrogenic complication of ovarian stimulation, usually self-limited, but occasionally life threatening. Although the pathophysiology of this syndrome has not been completely elucidated, the underlying mechanism responsible for the clinical manifestations of OHSS appears to be an increase in capillary permeability of mesothelial surfaces. Many preventive strategies have been tried but there is as yet no means of completely preventing it. Objective: To prevent ovarian hyperstimulation syndrome (OHSS) in high risk patients undergoing intracytoplasmic sperm injection (ICSI) cycles by using diosmin and cabergoline. Patients and Methods: This study was conducted on 100 infertile female patients of high risk for developing OHSS undergoing intra-cytoplasmic sperm injection (ICSI) cycle.The cases were then be divided into2 groups:(Group A will be given 2 tab (500mg)/8hs diosmin orally, for two weeks starting at the day of HCG injections and group B will recieve 1 tab. (0.5 mg)/day cabergoline orally for 14 days starting at day of HCG injection). All patients accepted and consented to the IVF/ICSI program Group. Results: Our results revealed that: there were no statistical significant differences between the two studied groups regarding BMI, patients' age, infertility duration, type and cause of infertility. Estradiol levels on day of HCG showed no statistical significant difference between the 2 groups with a mean of 4343.5 ± 628.53 and 4390.6 ± 724.9 for diosmin and cabergoline groups respectively. Among the two studied groups, there was no statistical significant difference between the mean of the number of oocytes retrieved and injected. Also there was no statistical significance as regards total number of embryos or embryos transferred between the two groups. In our study, hospitalisation rate showed no significant difference in diosmin and cabergoline-treated groups (6%, 12% respectively). Conclusion: The primary approach in the prevention of OHSS involved individualized ovarian stimulation protocols, judicious administration of gonadotropins, and careful monitoring of follicular development and serum E2 level. Using dopamine agonists of the strategies discussed, the incidence of OHSS can be significantly reduced. However, none of the strategies is universally successful.