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What Are Preeclampsia and Eclampsia ?

Preeclampsia and eclampsia are forms of high blood pressure that occur during pregnancy. As the names suggest, these two disorders are related. Preeclampsia, also called toxemia, may develop into the more severe eclampsia, which includes symptoms of preeclampsia together with seizure. These conditions, when they develop, usually occur during the second half of pregnancy (after 20 weeks), though sometimes they develop shortly after delivery and, in very rare situations, they occur before 20 weeks of pregnancy.

It is dangerous to allow blood pressure to stay high during pregnancy. High blood pressure may interfere with the placenta's ability to deliver oxygen and nutrition to your fetus, so your baby may be born weighing less than normal and may have other health problems. These pregnancies may need to be delivered early or by cesarean section. If your blood pressure continues to get higher and higher, your kidneys may have trouble functioning. You may have changes in the makeup of your blood, such as destruction of red blood cells (causing anemia), disturbed liver function, and decreased platelets (blood cells involved in clotting). Too few platelets can increase your risk of bleeding uncontrollably during delivery or even spontaneously. Your blood pressure may continue to climb, and you may develop seizures.

Once you begin to have seizures, you are considered to have eclampsia. This is a life-threatening situation for both you and your baby. During a seizure, you and your baby are at risk of being deprived of oxygen. In addition, the high blood pressure may cause the placenta to begin to separate from the wall of the uterus (called abruptio placentae). This can cause severe bleeding and death of the fetus and possibly the mother.

Who Gets Preeclampsia?

Preeclampsia affects 5-8% of all pregnancies. Any pregnant woman can get preeclampsia, but you are at increased risk of developing the condition if:

• This is your first pregnancy.
• Your mother or sister had preeclampsia or eclampsia during pregnancy.
• You are carrying twins.
• You are African American.
• You are younger than 20 or older than 40 at the time of pregnancy.
• You already have high blood pressure, kidney disease, or diabetes.
• You have a pre-pregnancy body mass index (BMI) greater than 30.

What Causes It?

The cause of preeclampsia is still unclear, although some studies have indicated it is related to poor nutrition. Other possible causes include injury to your blood vessels, a disruption in the hormones that maintain your blood vessels or lack or magnesium or calcium. Eclampsia usually develops when preeclampsia goes unnoticed and treated.