If you have high blood pressure (hypertension), the pressure of the blood in your blood vessels (arteries) is too high. Blood pressure is recorded as two figures. For example, 140/85 mm Hg. This is said as "140 over 85". Blood pressure is measured in millimetres of mercury (mm Hg). The first (or top) number is your systolic blood pressure. This is the pressure in your arteries when your heart contracts. The second (or bottom) number is your diastolic blood pressure. This is the pressure in your arteries when your heart rests between each heartbeat.
This is a companion discussion topic for the original article at https://patient.info/pregnancy/pregnancy-complications/high-blood-pressure-in-pregnancy