 Women in the menopause transition perimenopause are exposed to extreme hormone variability, tend to experience a unique set of severe stressors e.g., divorce, death of loved ones, and are also at substantially elevated risk to suffer from mood and anxiety disorders. The purpose of this research is to understand the mechanisms by which variability in estradiol E2 is associated with the symptoms of anxiety and anhedonia loss of interest and pleasure - a common symptom of depression. By stabilizing E2 variability with a hormonal manipulation, this research will determine the degree to which the E2 variability or E2 levels plays a causal role in perimenopausal anxiety and anhedonia symptoms and whether it does so by affecting biological responses to stress. 