Estrogen, estrogen treatment and the post-reproductive woman's brain

From early embryonic life to death, estrogen is a primary regulator of brain neurogenesis and cell number, synaptogenesis and synaptolysis, multiple cognitive and autonomic functions, vascular function, immune responses and defense measures against brain lesions and dystrophy. Although recent attention has focused on the roles of estrogen during the climacteric, knowing estrogen's role in brain development and reproductive function is necessary to understand what happens when this powerful influence is removed during the climacteric. This review will therefore address the full picture, with stress on the later-life role of estrogen in the brain.