What is high blood pressure (hypertension)?

Blood pressure is the measurement of the pressure or force of blood pushing against blood vessel walls. In high blood pressure (hypertension), this pressure against the blood vessel walls is consistently too high. High blood pressure is often called the “silent killer” because you may not be aware that anything is wrong, but the damage is occurring within your body.

What can happen if high blood pressure is not treated?

Untreated hypertension may lead to serious health problems including:

Who is most likely to have high blood pressure?

You are more likely to have high blood pressure if you:

  • Have family members who have high blood pressure, cardiovascular disease or diabetes.
  • Are African American.
  • Are over age 55.
  • Are overweight.
  • Don’t get enough exercise.
  • Eat foods high in sodium (salt).
  • Smoke.
  • Are a heavy drinker (more than two drinks a day in men and more than one drink a day in women).

How do I know if I have high blood pressure?

High blood pressure usually doesn’t cause symptoms. The only way to know if you have high blood pressure is to have your blood pressure taken. Know your numbers so you can make the changes that help prevent or limit damage.

Your blood pressure reading has two numbers. The top number is the systolic, which measures the pressure on the blood vessel walls when your heart beats. The bottom number is the diastolic, which measures the pressure on your blood vessels between beats when the heart is at rest.

For example, a reading of 110/70 is within normal range for blood pressure; 126/72 is an elevated blood pressure; a reading of 135/85 is stage 1 (mild) hypertension, and so on (see table).

CategoryBlood Pressure
NormalUnder 120/80 mmHg
Elevated Blood Pressure120-129/less than 80 mmHg
Stage I Hypertension (mild)130-139/OR diastolic between 80-89 mmHg
Stage 2 Hypertension (moderate)140/90 mmHg or higher
Hypertensive Crisis (get emergency care)180/120 mmHg or higher

Can high blood pressure affect pregnancy?

High blood pressure complicates about 10% of all pregnancies. There are several different types of high blood pressure during pregnancy and range from mild to serious. The forms of high blood pressure during pregnancy include:

Chronic hypertension: High blood pressure which is present prior to pregnancy.

Chronic hypertension with superimposed preeclampsia: Preeclampsia, which develops in someone who has chronic hypertension (high blood pressure before pregnancy).

Gestational hypertension: High blood pressure in the latter part of pregnancy, but no other signs or symptoms of preeclampsia are present. Some women will later develop preeclampsia, while others probably have high blood pressure (chronic hypertension) before the pregnancy.

Preeclampsia: This is found in the latter half of pregnancy and results in hypertension, protein in the urine and generalized swelling in the mother. It can affect other organs in the body and cause seizures (eclampsia).

Your blood pressure will be checked regularly during prenatal appointments, but if you have concerns about your blood pressure, be sure to talk with your provider.

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