What is Eclampsia?
Written by Amanda Wattson, MD   
Tuesday, 13 October 2009
Preeclampsia is high blood pressure that develops or increases during pregnancy. Eclampsia is a complication of severe preeclampsia that involves seizures.
What is going on in the body?

The placenta is the spongy material in the mother's uterus that nourishes the fetus. Some experts believe that a problem with the placenta causes preeclampsia. The mother has spasms of the blood vessels, which increase her blood pressure. The blood flow to the placenta is impaired. If the blood pressure is not controlled, it can damage the placenta and cause the death of the fetus.

Preeclampsia develops in 5% of pregnant women. It usually occurs after the 20th week of pregnancy. It may be mild or severe. The high blood pressure can affect the brain, kidneys, liver, and lungs. If the high blood pressure in the brain causes bleeding into the brain, the woman may have seizures. This complication is called eclampsia.

One in 200 pregnant women who have preeclampsia will go on to have eclampsia. The seizures of eclampsia are marked by general abnormal electrical activity in the brain. Usually the seizures start before the baby is born. However, about 20% to 25% of the time, seizures begin within the first 24 hours after the baby is born. A few women develop seizures later, up to 3 weeks after the birth.
What are the causes and risks of the condition?

Factors that increase a woman's risk of preeclampsia are:
- a first pregnancy
- African American ethnicity
- diabetes
- high blood pressure before pregnancy
- low socioeconomic status
- maternal age below 20 or over 35
- molar pregnancy, an abnormal condition that mimics a normal pregnancy but is actually a tumor
- multiple gestation such as twins or triplets
- preeclampsia or eclampsia in previous pregnancies
- she or the baby's father was born of a pregnancy with preeclampsia or eclampsia
- underlying kidney disease

No one knows why some women with preeclampsia develop the seizures associated with eclampsia. Theories about why seizures might occur in pregnancy involve:
- small clots that block blood vessels in the brain and restrict oxygen
- narrowing of tiny arteries in the brain
- areas of bleeding in the brain
- high blood pressure
- dietary risks
- genetic risks
- a problem with the brain or nervous system

What are the treatments for the condition?

Eclampsia is treated by delivering the baby. If the baby is older than 28 weeks, a cesarean section is usually done. During a C-section, the baby is delivered through an incision made in the abdomen. Prolonging the pregnancy can harm the mother or cause the baby to die.

Before a C-section is done, the mother's seizures and blood pressure may need to be controlled with medicines. Magnesium sulfate is the medicine of choice to prevent and control seizures. Diazepam may be used if the magnesium sulfate doesn't stop seizures. Medicines such as hydralazine and labetalol can be used to lower the blood pressure.
What are the side effects of the treatments?

A C-section may cause bleeding, infection, or even death. Medicines used to treat eclampsia may cause low blood pressure, breathing difficulties, nausea, or allergic reactions.
What happens after treatment for the condition?

After the baby is born, a woman may still have seizures for up to 6 weeks. Her provider will closely monitor blood pressure, urine and blood tests, and any other symptoms. If a baby is born prematurely and has health problems, hospitalization and care will be needed.
How is the condition monitored?

Preeclampsia often recurs in later pregnancies. Early prenatal care is key to recognizing warning signs and managing the condition. Any new or worsening symptoms should be reported to the healthcare provider.