Surgical menopause, estrogen, and cognitive function in women: what do the findings tell us?

Randomized, controlled trials of estrogen treatment found protective effects of estrogen therapy (ET) on verbal memory in healthy, 45-year-old surgically menopausal women given 17-beta estradiol immediately after surgery. However, no effect was found when conjugated equine estrogens were given to older women years after their surgical menopause. These findings suggest that there is a critical time for the initiation of estrogen following the menopause with regard to its protective effect on memory as well as a specificity of the effect on verbal memory. These factors may explain why no protective effect of ET on cognitive aging was found in the Women's Health Initiative Memory Study.