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Preeclampsia and Eclampsia


Antonette T. Dulay

, MD, Main Line Health System

Reviewed/Revised Oct 2022

Preeclampsia is new high blood pressure or worsening of existing high blood pressure that is accompanied by excess protein in the urine and that develops after the 20th week of pregnancy. 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, drugs to lower blood pressure, or delivery of the baby.

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

Pregnancy complications, such as preeclampsia and eclampsia, are problems that occur only during pregnancy. They may affect the woman, the fetus, or both and may occur at different times during the pregnancy. However, most pregnancy complications can be effectively treated.

About 3 to 7% of pregnant women develop preeclampsia. In preeclampsia, an increase in blood pressure is accompanied by protein in the urine (proteinuria). Preeclampsia can suddenly cause seizures Seizure Disorders In seizure disorders, the brain's electrical activity is periodically disturbed, resulting in some degree of temporary brain dysfunction. Many people have unusual sensations just before a seizure... read more (eclampsia). Eclampsia occurs in fewer than 1% of women with severe preeclampsia. If not treated promptly, eclampsia is usually fatal.

Preeclampsia (with or without eclampsia) develops after the 20th week of pregnancy and usually before the end of the first week after delivery. One fourth of the cases occur after delivery, usually within the first 4 days but sometimes up to 6 weeks after delivery.

Did You Know...

  • Preeclampsia and eclampsia can develop after delivery.

HELLP syndrome

The HELLP syndrome develops in 1 or 2 of 10 women with severe preeclampsia or eclampsia. The HELLP syndrome consists of the following:

  • Hemolysis (the breakdown of red blood cells)

  • Elevated levels of liver enzymes, indicating liver damage

  • A low platelet count, making blood less able to clot and increasing the risk of bleeding during and after labor

Most pregnant women with the 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. But it is more common among women who

Symptoms of Preeclampsia and Eclampsia

Some women with preeclampsia have no symptoms. In others, preeclampsia causes fluids to accumulate (edema Swelling Swelling is due to excess fluid in the tissues. The fluid is predominantly water. Swelling may be widespread or confined to a single limb or part of a limb. Swelling is often in the feet and... read more Swelling ), particularly in the hands, fingers, neck, and face and around the eyes but also in the feet. Rings may no longer fit. Women may gain excess weight quickly, sometimes more than 5 pounds a week.

Tiny red dots (petechiae) may appear on the skin, indicating bleeding in the skin.

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)

If the HELLP syndrome develops, it may cause similar symptoms. The HELLP syndrome can develop before symptoms of preeclampsia appear.

If a pregnant woman has a new headache that does not resolve or lessen with acetaminophen or her ring no longer fits her finger, she should call her doctor.

Did You Know...

  • If the ring of a pregnant woman no longer fits her finger, 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. They may even die. 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 Placental Abruption Placental abruption is the premature detachment of the placenta from the wall of the uterus, usually after 20 weeks of pregnancy. Women may have abdominal pain and tenderness and vaginal bleeding... read more ). 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:

  • Typical symptoms such as headache, swelling around her eyes, and particularly swelling of her hands

  • Increased blood pressure during the pregnancy

  • Protein in the urine

Doctors do blood and urine tests to confirm the diagnosis, to determine how severe preeclampsia is, and to check for organ damage.

Doctors also monitor the fetus Fetal monitoring Labor is a series of rhythmic, progressive contractions of the uterus that gradually move the fetus through the lower part of the uterus (cervix) and birth canal (vagina) to the outside world... read more . 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 drugs to treat high blood pressure

  • Delivery, depending on the severity of preeclampsia and well-being and age of the fetus

  • Sometimes magnesium sulfate to prevent or stop seizures

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

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

If needed, women are first treated with drugs to lower blood pressure Medications Used to Treat Heart and Blood Vessel Disorders During Pregnancy (antihypertensive drugs) and drugs to control seizures. Then delivery is usually done as soon as possible in the following situations:

  • Pregnancy that has lasted 37 weeks or more

  • Eclampsia

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

  • Worsening organ damage in the woman

  • HELLP syndrome

  • Problems in the fetus

If delivery can be safely delayed in pregnancies of less than 34 weeks, women are given corticosteroids to help the fetus's lungs mature. Corticosteroids may be given during 34 to 36 weeks of pregnancy if women have not received them earlier in the pregnancy and have stable vital signs.

Preeclampsia that does not cause severe symptoms

If preeclampsia does not cause severe symptoms and occurs before 37 weeks of pregnancy, women can be treated as outpatients. They are advised to modify their activities. For example, they are advised to stop working if possible, stay seated most of the day, and avoid stress. Also, these 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 the woman and the fetus are not at risk of severe problems. These women may be able to go home, but they must be frequently evaluated by their doctor. If they go home, they must come into the doctor's office to have a nonstress test at least twice a week. For nonstress testing, the fetus’s heart rate is electronically monitored while the fetus lies still and as it moves. Amniotic fluid is measured at least once a week. Blood tests used to evaluate preeclampsia are usually done once a week.

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

Severe preeclampsia and eclampsia

As soon as eclampsia is diagnosed, women are given magnesium sulfate intravenously to prevent or stop seizures. If women have severe preeclampsia, they may be given magnesium sulfate to prevent seizures.

If women have seizures after being given magnesium sulfate, an antiseizure drug (diazepam or lorazepam) is given intravenously. Also, women may be given a drug to lower blood pressure (hydralazine or labetalol). These drugs are given intravenously.

The baby may be delivered by cesarean Cesarean Delivery Cesarean delivery is surgical delivery of a baby by incision through a woman’s abdomen and uterus. In the United States, up to 30% of deliveries are cesarean. Doctors use a cesarean delivery... read more Cesarean Delivery , which is the quickest way, unless the cervix is already opened (dilated) enough for a prompt vaginal delivery. A prompt delivery reduces the risk of complications for the woman and fetus. If the pregnancy has lasted at least 34 weeks and severe preeclampsia is diagnosed, delivery is recommended.

Before 34 weeks, women may be observed, usually in the hospital, if doctors think this approach is safe. In such cases, corticosteroids may be given to help the fetus's lungs mature.

If HELLP syndrome develops, the baby is usually delivered immediately, regardless of how long the pregnancy has lasted.

After delivery

After delivery, women who have had severe preeclampsia or eclampsia are given magnesium sulfate for 24 hours and closely monitored because they are at increased risk of seizures. Magnesium sulfate may or may not be given to women without severe preeclampsia.

After women finish taking magnesium sulfate or if they did not take it, women can resume as much as activity as they can tolerate.

Length of the hospital stay depends on whether complications develop. Most pregnant women do well after delivery and can usually go home in 2 days after a vaginal birth or in 3 to 4 days after a cesarean delivery. Some women may need antihypertensive drugs for all or part of the 6-week period after delivery (called the postdelivery period Hospital (What to Expect) The 6 weeks after pregnancy and delivery of a baby is called the postpartum period, when the mother’s body returns to its prepregnancy state. After childbirth, a mother can expect to have some... read more ), depending on how high their blood pressure is.

Most women who have had preeclampsia or eclampsia must see the doctor every 1 to 2 weeks after delivery in addition to the routine 6-week visit. If any blood or urine test results are abnormal, tests should be repeated at the 6-week visit. If results are persistently abnormal, women may be referred to a specialist.

In future pregnancies, taking a low dose of aspirin (baby aspirin) once a day starting in the 1st trimester can reduce the risk that preeclampsia will recur.

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