Blood pressure
One of the core features of pre-eclampsia is high blood pressure. Blood pressure is a measurement of two numbers. If either the top number (systolic blood pressure) is greater than 140 mmHg or the bottom number (diastolic blood pressure) is greater than 90 mmHg, then the blood pressure is higher than the normal range and the person has high blood pressure. If the systolic blood pressure is greater than 160 or the diastolic pressure is greater than 110, the hypertension is considered to be severe.