Antihypertensive therapy is administered to prevent stroke, which accounts for 15 to 20 percent of deaths from eclampsia. A common threshold for initiating antihypertensive therapy is sustained diastolic pressures greater than 105 to 110 mmHg or systolic blood pressures ≥160 mmHg, although the validity of these thresholds has not been tested prospectively. The risk of stroke correlates with the degree of elevation in systolic and diastolic pressures and maternal age