Midlife women are burdened with depression risk that is at least partly attributed to changing reproductive steroid dynamics across a prolonged reproductive transition. The investigators hypothesize that declining endogenous allopregnanolone (ALLO) levels across the menopause transition underlies perimenopausal depression. This mechanistic trial aims to amplify the contrast between lower endogenous ALLO levels in perimenopausal women and higher levels experimentally induced by exogenous ALLO. This will be achieved by using the exogenous ALLO treatment, brexanolone, which is FDA-approved to treat depression in postpartum patients, in a randomized, double-blind, parallel-arm, placebo-controlled trial. By manipulating ALLO levels together with key measurement of depression domains, this study harnesses the endocrine biology of perimenopause to explicate behavioral and neurobiological mechanisms underlying depression in perimenopausal women.
