Abstract —The mechanisms underlying the increased cardiovascular risk after menopause are incompletely known. To investigate whether menopause may induce left ventricular structural and functional adaptations in normotensive and hypertensive women, we compared in a case-control setting (1) 76 untreated hypertensive premenopausal women with 76 postmenopausal women and (2) 30 normotensive premenopausal women with 30 postmenopausal women. Subjects were individually matched by age (±5 years; range, 45 to 55), clinic systolic blood pressure (±5 mm Hg), and body mass index (±2 kg×m −2 ). All subjects underwent 24-hour blood pressure monitoring and M-mode echocardiography. Age, clinic and daytime blood pressure, body mass index, and smoking habits did not differ between the paired groups. After menopause, blood pressure fall from day to night was lower in both normotensives (10/15% versus 16/21%) and hypertensives (12/17% versus 16/21%) (all P <0.01). Menopause was also associated with a greater left ventricular relative wall thickness (38.8% versus 35.1% in normotensives, 40.2% versus 37.5% in hypertensives) and a reduced midwall fractional shortening (17.3% versus 18.6% in normotensives, 16.6% versus 17.9% in hypertensives) (all P <0.05). We conclude that menopause is associated with blunted day-night blood pressure reduction, impaired left ventricular systolic performance, and concentric left ventricular geometric pattern. These finding are independent of presence or absence of high blood pressure.