Blood pressure is the force of blood pushing against the walls of your arteries as the heart pumps. It's written as two numbers in mmHg — systolic (the higher number, when the heart beats) over diastolic (the lower number, when the heart rests). A reading around 120/80 mmHg is often used as a general reference point.
Persistently high blood pressure — hypertension — is a major risk factor for heart disease, stroke and kidney problems, and it usually causes no symptoms, so it must be measured. Blood pressure often rises after menopause. Diagnosis is based on repeated readings and your overall context, with a clinician. See high blood pressure in women.