Effect of experimental uremia upon the estrous cycle in rats

By daily vaginal smears, uremic rats showed significantly greater prevalence of irregular estrous cycles compared with sham-operated controls (p less than 0.02). There seems to be a correlation between the degree of renal failure and estrous cycle abnormalities. The lack of LH surge on the afternoon of proestrus, found in uremic animals, suggests a defect in the positive hypothalamic steroid feedback.