To compare the rate of development of buttock claudication in patients undergoing aortoiliac aneurysm repair with and without exclusion of antegrade hypogastric arterial flow. In the absence of convincing data, questions remain regarding the best management of hypogastric arterial (HA) flow to prevent the theoretical risk of buttock claudication.The Veterans' Affairs Open Versus Endovascular Repair (OVER) Cooperative Study prospectively collected information on buttock claudication. Trial participants were specifically prompted both pre- and postoperatively to report the development of claudication symptoms at several anatomic levels. Of note, trial investigators were specifically trained to occlude the trunk HA preserving the anterior and posterior divisions. Bayesian survival models were created to evaluate time to development of left, right or bilateral buttock claudication according to the presence/absence of antegrade hypogastric perfusion.881 patients from the OVER trial with information regarding status of hypogastric flow were included in the analysis. 788 patients maintained bilateral antegrade hypogastric arterial perfusion, 63 had right hypogastric coverage/occlusion, 27 had left hypogastric coverage/occlusion while 3 patients had bilateral hypogastric coverage/occlusion. Just under 5% (n=41) of all patients developed buttock claudication. After adjustment for smoking, COPD, medications, study arm, preoperative activity level, BMI, age and diabetes, intervention-related changes to hypogastric perfusion had no effect on time to development of buttock claudication. A Maximum A Posteriori Kullback- Leibler misfit chi-square was 14.45 with 24 degrees of freedom resulting in a goodness of fit p-value of p=0.94, indicative of a good fit.OVER is the largest aneurysm treatment study to prospectively collect data related to the development of claudication as well as hypogastric preservation status. Despite this, we were unable to find evidence to support the assertion that preservation of antegrade hypogastric flow decreases the rate of development of buttock claudication symptoms. The low rate of development of buttock claudication overall and in the subgroups is striking.