If you have chronic high blood pressure (hypertension), you can lower your blood pressure before pregnancy by exercising, eating a diet low in sodium and rich in fruits and vegetables, and staying at a healthy weight. Lowering your blood pressure reduces your risk of preeclampsia.

When you are pregnant, regular checkups are key to early detection and treatment. Prompt treatment is vital to preventing the development of severe and possibly life-threatening preeclampsia.

Recent preeclampsia research suggests that calcium supplements and low-dose aspirin offer a preventive benefit, especially for high-risk women.

Calcium supplements may reduce the risk of developing preeclampsia and the risk of having a low-birth-weight baby, particularly among high-risk women who normally don't get enough calcium.⁸ Taking a calcium supplement may also lower the risk of moving from mild to severe preeclampsia.²⁰ Other experts have found that there is no benefit from taking calcium.¹

All pregnant women can generally benefit from taking the U.S. Food and Drug Administration's recommended daily allowance of 1200mg of calcium per day.

Low-dose aspirin (antiplatelet) therapy may be a moderately effective preventive treatment for women at risk of developing preeclampsia. A review of studies involving over 36,000 pregnant women showed that taking antiplatelet medicine lowered their risk of preeclampsia, preterm birth related to preeclampsia, and fetal or newborn death related to preeclampsia.²¹ Although some experts question how effective low-dose aspirin is, others assert that high-risk women who take it regularly as directed do significantly lower their preeclampsia risk.²² Talk to your doctor or nurse-midwife about whether this treatment is right for you.

Research shows that taking vitamin C or vitamin E supplements does not help prevent preeclampsia.^{23, 24}