Delivery may affect arterial elasticity in women.

BACKGROUND Estrogen is considered to be cardioprotective, but estrogen replacement therapy for postmenopausal women has not shown results for either primary or secondary cardiovascular event prevention. During normal pregnancy, women have significantly higher levels of estrogen and it may be endogenous estrogen that helps prevent atherosclerosis. METHODS AND RESULTS The present cross-sectional study examined the association between pregnancy followed by delivery and clinical atherosclerosis using the brachial-ankle pulse wave velocity (PWV). A total of 2,560 women undergoing annual health screening at the Institute of Hyogo Prefecture Health Promotion Association in Japan were recruited. Pregnancy history (the age of menarche/menopause and the number of gravida/para), conventional coronary risk factors, and brachial-ankle PWV were recorded. Multivariate linear regression by stepwise selection analysis demonstrated that women who had 1 or more deliveries had a significantly lower PWV, independent of age and other conventional coronary risk factors. CONCLUSIONS Pregnancy followed by delivery may decrease arterial stiffness and prevent the progress of atherosclerosis in women. The contribution of such a pregnancy followed by delivery-related decrease in arterial stiffness to the reduction of cardiovascular disease in women should be further evaluated.