effect of soy isoflavone on hot flushes, endometrial thickness, and breast clinical as well as sonographic features

Background: phytoestrogens treatment to relieve hot flushes in menopausal women was considered recently. however, the actual effectiveness and safety are not clear. methods: randomized clinical trial (irct#20100706004329n5) was performed in 204 patients who com-plained of hot flushes in arash women's hospital, tehran, iran from 2013-2015. the first group received 50 mg isoflavone (group a) once daily and the second group received placebo (group b) in the same regimen. pa-tients were evaluated for breast examination (be) and breast sonography (bs) as well as vaginal sonography at initial presentation and at 6th and 12th week follow-ups. patients were educated to record frequency and se-verity of hot flushes. results: group a experienced less hot flushes attack (6 vs 9 patients with 5< attacks in 6 wk (p= 0.05), 7 vs 13 patients with 5< in 12 wk (p=0.01)) which was also less severe (8 vs 12 patients with severe symptoms in 6 wk (0.04) and 3 vs 10 patients with severe symptoms in 12 wk (0.001). isoflavone had no effect on neither breast density nor nodularity (in 6 wk, p=0.50 and 0.80, respectively and in 12 wk, p=0.32 and 0.43) and nei-ther breast tenderness nor nipple discharge (in 6 wk, p=0.40 and 0.34 respectively and in 12 wk, p= 0.31 and 0.26). there were no significant differences in endometrial thickness in 6 and 12wk. conclusion: effects of isoflavone on frequency and severity of hot flushes in perimenopausal women is ob-served. some clinical and ultrasonographic benign non-significant changes of the breast and endometrium are noted after isoflavone intake.