Preeclampsia and Eclampsia

ByAntonette T. Dulay, MD, Main Line Health System
Reviewed/Revised Apr 2024
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Preeclampsia is either new high blood pressure or worsening of existing high blood pressure that develops after the 20th week of pregnancy and is accompanied by excess protein in the urine. Eclampsia is seizures that occur in women with preeclampsia and that have no other cause.

  • Preeclampsia can cause the placenta to detach and/or the baby to be born too early, increasing the risk that the baby will have problems soon after birth.

  • The woman’s hands, fingers, neck, and/or feet may swell, and if preeclampsia is severe and not treated, she may have seizures (eclampsia) or organ damage.

  • Depending on how severe preeclampsia is, treatment may involve modified activity (bed rest), hospitalization, medications to lower blood pressure, or delivery of the baby.

  • Magnesium sulfate is given by vein to prevent or stop seizures.

In preeclampsia, an increase in blood pressure is accompanied by protein in the urine (proteinuria). Preeclampsia can suddenly cause seizures (eclampsia). If not treated promptly, eclampsia is usually fatal.

Preeclampsia (with or without eclampsia) develops after the 20th week of pregnancy, although most cases occur after 34 weeks of pregnancy. Some cases develop after delivery, most often within the first 4 days but sometimes up to 6 weeks after delivery. Preeclampsia occurs in approximately 5% and eclampsia occurs in less than 2% of deliveries worldwide.

Did You Know...

  • Preeclampsia and eclampsia can develop after delivery.

A variant of preeclampsia called HELLP syndrome develops in less than 1% of pregnancies. Women with HELLP syndrome have hemolysis (breakdown of red blood cells), elevated liver tests, and a low platelet count. Most pregnant women with HELLP syndrome have high blood pressure and protein in the urine, but some have neither.

Causes of Preeclampsia and Eclampsia

The cause of preeclampsia is unknown. Preeclampsia is more common among women with the following disorders or characteristics:

Symptoms of Preeclampsia and Eclampsia

Some women with preeclampsia have no symptoms. In others, preeclampsia causes fluids to accumulate (edema), particularly in the hands, fingers, and face and also in the ankles and feet. Rings may no longer fit. Women may gain weight quickly, sometimes more than 5 pounds a week.

If severe, preeclampsia can damage organs, such as the brain, kidneys, lungs, heart, or liver. Symptoms of severe preeclampsia include the following:

  • Severe headaches

  • Distorted vision

  • Confusion

  • Overactive reflexes

  • Pain in the upper right part of the abdomen (over the liver)

  • Nausea and/or vomiting

  • Difficulty breathing

  • Decreased urination

  • Very high blood pressure

  • Stroke (rarely)

Did You Know...

  • If a pregnant woman has sudden swelling of her hands or face, she should call her doctor.

Preeclampsia may cause few noticeable symptoms for a while, then suddenly worsen and cause seizures (eclampsia).

Babies may be small because the placenta malfunctions or because they are born prematurely. Complications of preeclampsia can even cause fetal death. Babies of women with preeclampsia are 4 or 5 times more likely to have problems soon after birth than babies of women who do not have this complication, depending on how early the baby is born and how much the baby weighs at delivery.

Rarely, preeclampsia may cause the placenta to detach too soon (called placental abruption). If preeclampsia and/or placental abruption occurs, the baby may be born too early, increasing the risk that the baby will have problems soon after birth.

Diagnosis of Preeclampsia and Eclampsia

  • A doctor's evaluation, including blood pressure measurement

  • Blood and urine tests

Doctors diagnose preeclampsia when a woman has the following:

  • Increased blood pressure during the pregnancy

  • Protein in the urine

Doctors do blood and urine tests to confirm the diagnosis and to determine how severe preeclampsia is. Doctors ask about symptoms and do blood tests or a chest x-ray to check for damage to organs (such as the lungs, liver, and kidneys).

Doctors also monitor the fetus. They check the fetus's heart rate. Ultrasonography is done to check other signs of the fetus's well-being, such as the amount of amniotic fluid and the fetus's size, movements, breathing, and muscle tone.

Treatment of Preeclampsia and Eclampsia

  • Usually hospitalization and sometimes medications to treat high blood pressure

  • Delivery, depending on the severity of preeclampsia, well-being of the mother and fetus, and weeks of pregnancy

  • Sometimes magnesium sulfate to prevent or stop seizures

Most women with preeclampsia are hospitalized. Women with severe preeclampsia or eclampsia are often admitted to a special care unit or an intensive care unit (ICU).

Delivery is the best treatment for preeclampsia, but doctors must weigh the severity of the preeclampsia and well-being of the mother or fetus (for example, whether the fetus is growing normally or is in distress) against the risk to the fetus of an early delivery.

If needed, women are first treated with medications to prevent seizures. Then delivery is usually done as soon as possible in the following situations:

  • Pregnancy has lasted 37 weeks or more

  • Eclampsia

  • Severe preeclampsia if the pregnancy has lasted 34 weeks or longer

  • Worsening organ damage in the mother

  • HELLP syndrome

  • Problems in the fetus

Before 34 weeks of pregnancy, women may be monitored closely, if doctors think monitoring instead of immediate delivery is safe. In such cases, corticosteroids may be given to the mother to help the fetus's lungs mature in preparation for an early delivery.

Preeclampsia that does not cause severe symptoms

If preeclampsia does not cause severe symptoms and occurs before 37 weeks of pregnancy, treatment and monitoring can be done through a doctor's office. Women should modify their activities. For example, they should stop working if possible, stay seated most of the day, and avoid stress. Also, women should see their doctor at least once a week.

However, most women with preeclampsia are hospitalized, at least at first. There, they are monitored closely to make sure they and their fetus are not at risk of severe problems. After an initial evaluation, some women may be able to go home and continue frequent visits with their doctor. These visits are usually weekly and include blood pressure measurements, blood tests, and testing the well-being of the fetus by monitoring the fetal heart rate pattern (called a nonstress test).

If preeclampsia does not become severe, at 37 weeks labor is usually induced and the baby is delivered.

Severe preeclampsia and eclampsia

Women with severe preeclampsia are admitted to the hospital and delivery is planned as soon as possible. The mother and fetus are monitored closely. Magnesium sulfate is given intravenously to prevent seizures (eclampsia) in the mother.

The baby is delivered by the method that is most appropriate for the situation. A prompt delivery reduces the risk of complications for the woman and fetus. If the cervix is already opened (dilated), labor may be induced to have a prompt vaginal delivery. A cesarean delivery may be done if it is the quickest way to complete the delivery.

After delivery

Blood pressure should be monitored closely until it normalizes after delivery. Women should see their health care professional for blood pressure measurement at least every 1 to 2 weeks after delivery. If blood pressure remains high 6 weeks after delivery, a woman may have chronic hypertension and should be referred to a primary care clinician for management.

aspirin) once a day starting in the first trimester can reduce the risk that preeclampsia will recur.

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