Effect of Soy Isoflavone on Hot Flushes, Endometrial Thickness, and Breast Clinical as well as Sonographic Features

  • Marziyeh VAHID DASTJERDI Dept. of Obstetrics and Gynecology, Arash Women's Hospital, Tehran University of Medical Sciences, Tehran, Iran
  • Bita ESLAMI Breast Disease Research Center (BDRC), Tehran University of Medical Sciences, Tehran, Iran
  • Maryam ALSADAT SHARIFI Dept. of Obstetrics and Gynecology, Arash Women's Hospital, Tehran University of Medical Sciences, Tehran, Iran
  • Ashraf MOINI Dept. of Obstetrics and Gynecology, Arash Women's Hospital, Tehran University of Medical Sciences, Tehran, Iran
  • Leila BAYANI Dept. of Radiology, Arash Women’s Hospital, Tehran University of Medical Sciences, Tehran, Iran
  • Hoda MOHAMMAD KHANI Dept. of Obstetrics and Gynecology, Vali-e-Asr Hospital, Tehran University of Medical Sciences, Tehran, Iran
  • Sadaf ALIPOUR Breast Disease Research Center (BDRC), Tehran University of Medical Sciences Dept. of Surgery, Arash Women's Hospital, Tehran University of Medical Sciences, Tehran, Iran
Keywords: Isoflavone, Hot flushes, Breast tissue, Endometrial thickness


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 complained 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. Patients 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 severity 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 neither 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 observed. Some clinical and ultrasonographic benign non-significant changes of the breast and endometrium are noted after isoflavone intake.



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How to Cite
VAHID DASTJERDI M, ESLAMI B, ALSADAT SHARIFI M, MOINI A, BAYANI L, MOHAMMAD KHANI H, ALIPOUR S. Effect of Soy Isoflavone on Hot Flushes, Endometrial Thickness, and Breast Clinical as well as Sonographic Features. Iran J Public Health. 47(3):382-389.
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