MRI有高敏感度可以提早發現乳腺組織異常。通常用於識別一個部位的增殖，血管增生（angiogenesis）及微血管的通透性（microvascular permeability），這可能表示早期乳腺腫瘤的形成。我們回顧了2005年台灣婦女的乳房MRI圖像，根據BI-RADS分類，將分為健康或不健康或需要覆檢。在我們的研究中，部分患者至少接受3個月含有雌激素成分或植物雌激素的雌激素補充劑。這些病人的影像也被分為健康或不健康或需要覆檢的群體。比較這兩組發現之間的有顯著性差異（P＜0.002）。某些情況下，比較MRI圖像，還可發現典型的雌激素／植物雌激素作用或撤回效果。MRI圖像上，反映過度使用雌激素或植物雌激素補充劑，會增加乳房的腺體組織增生。此增生可能會增加未來的乳癌患者的風險。

MRI provides a highly sensitive technique for early detection of abnormal breast tissue. It is useful for identifying a status of proliferation, angiogenesis, and microvascular permeability, which may indicate early breast neoplasm formation. We retrospectively studied 2005 breast MRI images from Taiwanese women and classified them as either healthy or unhealthycall backs for re-examination, according to BI-RADS categories. A subgroup of our study patients had received estrogen supplements, containing estrogen components or phytoestrogen, for at least 3 months. These patients' images were also classified into the unhealthycall backs for re-examination groups. These two groups were compared and a significant difference was found between them (P＜0.002). Comparison of the MRI images also identified certain cases in which there was a typical estrogen/phytoestrogen effect or a withdrawal effect. The overuse of estrogen or phytoestrogen supplements can increase breast glandular tissue proliferation, as reflected on MRI images. Such proliferation may increase the patient's risk of future breast cancer.