Hormones and cardiovascular health in women

Cardiovascular diseases (CVDs) may have their origin before birth: the combination of being small at birth and having an overly rich post-natal diet increases the likelihood of obesity and of acquiring a specific metabolic syndrome in adulthood that carries an increased risk of CVD. The incidence of CVD and mortality is very low in women of reproductive age but rises to a significant level in older women. In this article, we discuss CVD in relation to hormonal contraception, pregnancy and polycystic ovarian syndrome (PCOS) in younger women and menopause in older women. Women with PCOS have a higher risk of diabetes and hypertension, but studies to date have not shown an effect on CVD events. Use of combined hormonal contraception has only small effects on CVD because of the low baseline incidence of myocardial infarction (MI), stroke and venous thromboembolism (VTE) among young women. Women with existing risk factors or existing CVD, however, should consider alternative contraception. In pregnancy, CVD is rare, although, in the West, it now accounts for a significant proportion of maternal mortality as the frequency of obstetrical causes of mortality has substantially declined. The frequency of VTE is 15 per 10 000 during pregnancy and the post-partum period. In older women, menopause causes a slightly higher risk of MI after allowing for age, although there is substantial heterogeneity in the results of studies on menopause and age at menopause and MI. A larger effect might have been expected, because estrogen reduces the risk of developing atherosclerosis in premenopausal women, whereas in post-menopausal women who may have established atherosclerotic disease, estrogen increases the risk of myocardial disease through the effects on plaque stability and clot formation. Recent trial results indicate that hormone treatment in menopause does not favourably affect the risk of MI, stroke or other vascular disease. Thus, prevention of CVD should rely on diet and fitness, low-dose aspirin and treatment of hypertension, hyperglycaemia and hyperlipidaemia.