Abstract Objective: The association between menopause and incident cardiovascular disease (CVD) is controversial. We evaluated the relationships of estrogen deficiency (ovarian reproductive aging) assessed by age at natural menopause (ANM), chronological aging, and antecedent CVD risk factors (biological aging) with left ventricular (LV) structure and function among women transitioning from pre- to postmenopause. Methods: We studied 771 premenopausal women (37% Black) from the Coronary Artery Risk Development in Young Adults Study with echocardiographic data in 1990 to 1991 (mean age: 32 y) who later reached natural menopause by 2015 to 2016 and had repeated echocardiographic measurements. Linear regression models were used to evaluate the association of ANM with parameters of LV structure and function. Results: Mean ANM was 50 (± 3.8) years and the average time from ANM to the last echocardiograph was 7 years. In cross-sectional analyses, a 1-year increase in ANM was significantly associated with lower postmenopausal LV mass (LVM), LVM indexed to body surface area, LV mass-to-volume ratio, and relative wall thickness. In age-adjusted longitudinal analyses, higher ANM was inversely associated with pre- to postmenopausal changes in LVM (β = –0.97; 95% CI: –1.81 to –0.13, P = 0.024) and LVM indexed (β = –0.48; 95% CI: –0.89 to –0.07, P = 0.021). Controlling for baseline LV structure parameters and traditional CVD risk factors attenuated these associations. Further adjustment for hormone therapy uses did not alter these results. Conclusion: In this study, premenopausal CVD risk factors attenuated the association of ANM with changes in LV structure parameters. These data suggest that premenopausal CVD risk factors may predispose women to elevated future CVD risk more than ovarian aging.