Oophorectomy prior to menopause is associated with late-life dementia. Memory decline may start within 6 months after oophorectomy in middle-aged women, suggested by lower verbal and working memory performance. Unknown is whether such changes persist beyond 6 months, and whether they are reversed by estradiol. Short-term benefits of estradiol on verbal memory following oophorectomy were observed in one study, but longer term effects remain unknown. In the present study, middle-aged BRCA1/2 mutation carriers with early oophorectomy at least 1 year prior to study onset were tested on verbal and working memory with results stratified by (1) current estradiol use (n = 22) or (2) no history of estradiol use (n = 24), and compared to age-matched premenopausal controls (n = 25). Both memory abilities were adversely affected by oophorectomy, but only working memory was maintained by estradiol. Estrogen metabolite levels correlated with working memory, suggesting a role for estradiol in preserving this ability. Memory decline appears to persist after early oophorectomy, particularly for women who do not take estradiol. (C) 2020 Elsevier Inc. All rights reserved.