What Is the Normal Blood Pressure for Females?

It's important to monitor your blood pressure regularly, and to modify your diet, lifestyle and levels of physical activity to maintain your blood pressure within normal ranges. Whether taking birth control pills, pregnant, menopausal or African American, maintaining normal blood pressure greatly reduces risk of heart attack and stroke in women of all ages.

Definition of Blood Pressure

• Blood pressure refers to the measurement of the force against the walls of your arteries as the heart pumps blood through your body. Every time your heart contracts, blood is "pressed" against the walls of the arteries and measured as systolic blood pressure (the first or top number). When the heart relaxes and refills with blood, the pressure on artery walls drops markedly. This relaxed state is measured as diastolic blood pressure (the second or bottom number).

Measuring Blood Pressure

• Blood pressure is taken using a stethoscope to listen to your blood flow and a cuff style sphygmomanometer, which is wrapped around the upper arm and pumped up. Pressing the release valve, air pressure in the cuff is slowly reduced until your doctor hears a thumping sound, indicating that blood is once again being forced through the brachial artery. This is recorded as the systolic or top number of your blood pressure. Air pressure on the cuff will continue to be released until no sound is heard, and this number will be recorded as your diastolic blood pressure.

Normal Blood Pressure

• Optimal blood pressure is considered to be 120/80 mmHg or below; however, blood pressure as high as 130/85 mmHg is still considered within normal ranges. A diagnosis of high blood pressure or hypertension is usually made after three or more consecutive readings are taken of 140/90 mmHg or above. Drug therapy is usually initiated.

  Note that the blood pressure ranges listed above apply to both men and women. However, women have special risks for developing high blood pressure. Drug manufacturer disclosure statements warn that birth control pills have been linked with high blood pressure in some women. Women prescribed the pill are warned not to smoke while taking it, especially if they suffer from mild kidney disease, have a family history of high blood pressure or are over the age of 35.

Black Women at Risk

• Statistically, African American women of all ages are more likely to have higher blood pressure than white women and to be more susceptible to hypertension and the associated health risks. There is no scientific evidence that proves why, however.

Blood Pressure in Pregnancy

• Some women develop high blood pressure suddenly during a pregnancy, which is a condition called gestational hypertension. A sudden rise in blood pressure can be serious and cause complications including premature delivery of the baby or low birth weight. A pregnant woman may also develop preeclampsia, which is a sudden increase in blood pressure that takes place after the 20th week of pregnancy. Preeclampsia can be life-threatening for both the unborn child and the mother, and obstetricians will often opt to deliver a baby early by Cesarean section.

Blood Pressure and Menopause

• Pre-menopausal women (generally below age 45) develop high blood pressure less frequently than men, believed to be due to the protective effects of the hormone estrogen. However, at about age 55 (when most females are through menopause and menstrual cycles have ceased completely), women have a much higher risk of developing hypertension than men.