Women and men share many of the same risk factors for stroke, although there are several risk factors that may be more prevalent in women than in men.

High blood pressure (hypertension) significantly raises any person’s risk of stroke. African-American and Alaska Native women are particularly likely to have high blood pressure. Consistent systolic/diastolic blood pressure levels over 120/80 mmHg (milligrams of mercury) increases stroke risk.

High levels of LDL (“bad”) cholesterol also raise the risk of stroke in both men and women. However, cholesterol levels in women tend to remain lower than men until after menopause, when women’s cholesterol may increase significantly. This places post-menopausal women at a higher risk of stroke.

Other risk factors that affect both women and men include age, family history, diabetes, smoking, coronary artery disease, atrial fibrillation (heart rhythm disorder), lack of exercise, obesity, head injury, excessive alcohol use, previous stroke or heart attack and history of transient ischemic attack (short-term interruptions in blood flow to the brain).

Research has identified a number of additional risk factors that may play a role in the development of strokes in women. They include:

• Loss of estrogen. After menopause, women’s lower estrogen levels can gradually increase the risk of stroke over time. Hormone replacement therapy (HRT) is used by millions of women to help replace the estrogen deficit that naturally occurs after menopause.
  
  However, some evidence suggests that use of HRT may also increase the risk of stroke. Therefore, many experts do not recommend that estrogen replacement therapy be used for the prevention of stroke. These findings match similar results from the Women’s Health Initiative, which found that HRT appeared to increase the risk of blood clots and stroke. Raloxifene – a drug used for the prevention and treatment of osteoporosis (loss of bone density) – appeared to significantly cut the risk of stroke among women at high risk for heart disease in post-menopausal women. Research continues on raloxifene and on the potential impact of hormone replacement therapy on stroke risk.
  
  
• Birth control pills. The low-dose oral contraceptives currently prescribed for birth control carry a much lower risk than earlier pills. However, they still carry an increased risk of stroke. The risk is more pronounced among smokers, women with a history of migraines and women over the age of 40.
  
  
• Pregnancy. Women’s risk of stroke increases during pregnancy and in the weeks just after delivery. During this time, women are particularly at risk for a hemorrhagic stroke.
  
  
• Antiphospholipid syndrome. Some women who have had frequent miscarriages suffer from a condition called antiphospholipid syndrome, which is a disorder that causes excessive blood coagulation. It also increases the risk of stroke.
  
  
• Migraines. Women who experience migraines have a 3 to 6 fold increase in stroke risk. Migraines occur more frequently in women than in men.

In addition, women of certain demographic groups may be more likely to have certain risk factors and to be at increased vulnerability for stroke. For example, studies show that African-American women tend to have substantially higher lipid (fat) profiles than women in other demographic groups. Lipid profiles are blood tests that measure a woman’s total cholesterol, HDL (“good”) cholesterol, LDL (“bad”) cholesterol and triglycerides. High readings indicate a substantial risk of blood-vessel blockage (e.g., coronary artery disease) that could result in stroke.

Overall, the risk of stroke in African-American/Black and Hispanic women is  higher than in Caucasian women, according to the American Heart Association. In fact, stroke and other diseases involving blood supply to the brain (cerebrovascular diseases) are the leading cause of death among African American women in the United States, according to the U.S. Department of Health and Human Services.