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Preeclampsia and Eclampsia


The Manual's Editorial Staff

Last full review/revision Sep 2019
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What are preeclampsia and eclampsia?

Preeclampsia is a certain type of high blood pressure that happens during pregnancy. The placenta (afterbirth) is the organ in your uterus (womb) that feeds your unborn baby (fetus). Preeclampsia can cause the placenta to pull away from your uterus too early. This can cause your baby to be born too early. A baby born too early is more likely to have problems soon after birth.

Eclampsia is when preeclampsia causes you to have seizures (when your body moves and jerks out of your control) and sometimes causes blood and liver problems. These problems can be life-threatening to you and your baby.

  • Preeclampsia can start any time after the 20th week of pregnancy or even within the first few days after delivery

  • Untreated preeclampsia can lead to eclampsia

  • Common signs of preeclampsia are swelling near your eyes and hands and protein in your urine—doctors will check your urine for protein at each pregnancy visit

  • The best way to treat preeclampsia is to deliver your baby

Doctors usually don't know why preeclampsia and eclampsia happen. However, they're more likely to happen when a pregnant woman:

  • Is pregnant for the first time

  • Had preeclampsia before

  • Is pregnant with more than one baby (such as twins or triplets)

  • Had high blood pressure before the pregnancy

  • Is younger than 17 or older than 35

What are the symptoms of preeclampsia?

You might not have any symptoms. Or you might have:

  • Swelling in your hands, feet, and face (especially around your eyes)

  • Tiny red dots on your skin

Very bad preeclampsia can cause:

  • Headaches—call your doctor if you have a new headache that doesn’t get better within 24 hours or after taking acetaminophen

  • Confusion

  • Vision changes

  • Trouble breathing

  • Belly pain and throwing up

  • Seizures (sudden, jerking motions)—this means you now have eclampsia

How can doctors tell if I have preeclampsia?

Doctors suspect preeclampsia based on your symptoms and if you have:

Doctors do blood tests and urine tests to tell for sure and figure out how bad it is. They’ll also check your baby’s heart rate, movements, and breathing.

How do doctors treat preeclampsia?

Treatment depends on how severe your preeclampsia is.

Mild preeclampsia

  • You'll probably stay in the hospital, at least at first

  • There, you'll stay in bed and be monitored closely until your baby grows enough to be delivered safely (around 36 weeks of pregnancy)

  • Doctors usually give you medicines to lower your blood pressure

  • If your blood pressure and other problems can be controlled, you may be able to go home but you'll have to rest and avoid stress

If preeclampsia develops near your due date, your doctor may give you medicine to start labor. You'll get an IV medicine (directly in your vein) called magnesium sulfate during labor to prevent seizures.

Very bad preeclampsia and eclampsia

  • You're hospitalized immediately

  • At the hospital, you'll be given IV magnesium sulfate to prevent or stop seizures

  • You may get IV medicine to lower your blood pressure

  • If you have seizures even after being given magnesium sulfate, you'll get another IV medicine to control seizures


Delivering the baby is the best way to stop very bad preeclampsia and eclampsia. You may need surgery to deliver your baby, called a cesarean section (C-section), which is the quickest way. If your cervix (the lower part of your uterus) is already opened enough for vaginal delivery to be quick, you may have a vaginal delivery.

After delivery

You'll get magnesium sulfate for 24 hours and be closely monitored for 2 to 4 days in the hospital.

After returning home

  • You may need to take medicines to lower your blood pressure

  • You'll have a checkup at least every 1 to 2 weeks for the first few months after delivery

  • Your blood pressure may remain high for 6 to 8 weeks after delivery

  • If it remains high longer, the cause may be unrelated to preeclampsia

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