Abstract: Premenopausal women have lower risk and incidence of hypertension and cardiovascular disease（CVD） compared to age-matched men and this sex advantage for women gradually disappears after menopause，suggesting that sexual hormones play a cardioprotective role in women. However，randomized prospective primary or secondary prevention trials failed to confirm that hormone replacement therapy（HRT） affords cardioprotection. This review highlights the factors that may contribute to this divergent outcome and could reveal why young or premenopausal women are protected from CVD and yet postmenopausal women do not benefit from HRT.

Key words: Estrogens, Estrogen replacement therapy, Cardiovascular diseases, Menopause, Prospective studies