Luteinizing hormone (LH) plays an important role in learning and memory as well as Alzheimer’s Disease (AD). Previously, our laboratory has demonstrated that there is an inverse relationship between blood and brain levels of LH and that when levels are normalized post-ovariectomy, both cognition and spine density losses are reversed. Because these differences appear to depend on the reproductive status of the mouse, we determined whether normal cyclic fluctuations in LH during the estrous cycle correlate with neuronal markers of neuroplasticity that are associated with cognition. To address this, we measured serum LH levels using sandwich RIA ELISAs and determined changes in synaptophysin and spinophilin in cognition-associated brain regions. As expected, preliminary data suggests that LH levels fluctuate during the estrous cycle and may correlate with synaptic markers associated with cognitive function. Given that others have found that cognition function fluctuates during the estrous cycle, our data demonstrates that these fluctuations may be at least, in part, dependent on changes in serum and brain LH.