After menopause, why does estrogen replacement therapy elevate the risk of endometrial hyperplasia?

💡 Explanation

Estrogen stimulates endometrial cell proliferation. Without progesterone to induce differentiation and limit growth, the endometrium can become hyperplastic; therefore, unopposed estrogen leads to overgrowth, rather than direct blood supply changes or altered LH secretion, because the mechanism is proliferative signaling.

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