What Is Preeclampsia?

Preeclampsia is a serious blood pressure condition that occurs during pregnancy or soon after giving birth. However, the condition not only causes high blood pressure but can also affect multiple organs in the body which may cause poor outcomes for both the birth parent and the baby. Complications are most likely to occur if you develop the condition before 34 weeks. 

There are some common risk factors for preeclampsia but some women develop it for unknown reasons. If you have a history of preeclampsia, you may be able to prevent it in future pregnancies. Regardless of which pregnancy you are in, however, healthcare providers can monitor and treat your condition to help you manage symptoms and prevent complications until your baby is born.

Types of Preeclampsia 

Preeclampsia is a form of hypertension (or, high blood pressure) that occurs during a pregnancy 20 weeks into the gestation period. While there aren’t different types of preeclampsia, experts can often categorize the condition into two groups, based on the severity of symptoms.

Mild Preeclampsia

Mild preeclampsia is the most common type, characterized by elevated blood pressure. You may also have a high level of protein in your urine, but that’s not required for a preeclampsia diagnosis. It's possible to experience mild symptoms of the condition or have no symptoms at all.

Severe Preeclampsia 

You might have severe preeclampsia if you meet the criteria for mild preeclampsia, but also have clear signs of organ dysfunction or damage. This may result in other health complications and will often require extended treatment.


Mild preeclampsia can be largely asymptomatic (meaning, you have no symptoms at all). You might only learn about your condition during a routine checkup with your obstetrician-gynecologist (OBGYN) or primary health care provider.

As preeclampsia progresses, the condition can begin to affect your organs and cause symptoms like:

Your provider may order further testing if they suspect you have severe preeclampsia. Additional tests may show signs of:

  • A low platelet count
  • Abnormal kidney or liver function
  • Fluid in your lungs


Preeclampsia causes high blood pressure, which can become severe and affect normal organ function. Because it’s directly related to pregnancy, it usually goes away once you deliver your baby (though some birthing parents develop preeclampsia soon after birth, rather than during pregnancy). About 5% to 8% of pregnant people develop preeclampsia. 

Experts don’t know for sure what causes preeclampsia, but some research suggests that a combination of genetics, preexisting medical conditions, nutritional deficiencies, and how your body responds to pregnancy can play a role. It's important to note that it’s generally well-known that the placenta plays some role in the development of preeclampsia, but experts don't yet know why and research remains ongoing.

Risk Factors

While some people get preeclampsia for unknown reasons, there are several things that can increase your risk. Research shows that Black women and birthing parents who have diabetes or autoimmune conditions (e.g., lupus or rheumatoid arthritis) are more likely to develop preeclampsia. If you have been pregnant and had preeclampsia before, you are also at a higher risk of developing it again in future pregnancies.

Other risk factors include:

  • Being under age 20 or over age 35
  • Being pregnant with more than one baby
  • Becoming pregnant from in vitro fertilization (IVF)
  • Having a personal or family history of high blood pressure or preeclampsia
  • Having a body mass index (BMI) of 30 or more

A Note About BMI

Body Mass Index, or BMI, is a biased and outdated metric that uses your weight and height to make assumptions about body fat, and by extension, your health. This metric is flawed in many ways and does not factor in your body composition, ethnicity, sex, race, and age. Despite its flaws, the medical community still uses BMI because it’s an inexpensive and quick way to analyze health data.


Your provider can diagnose you with preeclampsia through a variety of tests. The most common measure is a blood pressure reading, but your provider can order a urinalysis or blood testing to look for signs of organ damage or severe preeclampsia.

  • Blood pressure reading: During your pregnancy, it's common to have several appointments with your provider to check in on your progress and the development of your baby. At these appointments, it's standard practice for your provider to measure your vitals (e.g., blood pressure, heart rate, and temperature). You may have mild preeclampsia if your blood pressure if you have a blood pressure of 140/90 mmHg (millimeters of mercury) or higher. If your blood pressure is 160/110 mmHg or higher, this could be a sign of severe preeclampsia. 
  • Urinalysis: Your provider can use a urinalysis—or urine test—to measure the amount of protein in your urine. Too much protein in your urine can be a sign of kidney damage or organ dysfunction, which can be a result of preeclampsia. In some cases, you may be asked to collect your own urine at home 24 hours before the appointment and bring it into your provider’s office for more comprehensive analysis.
  • Blood testing: It's common practice for providers to regularly test your blood during pregnancy. They do this to assess your liver and kidney function, which can help measure the severity of preeclampsia and any damage the condition may have caused.


In most cases, the best treatment for preeclampsia is delivering the baby on time. However, this might not always be possible, especially if you develop mild preeclampsia before 37 weeks of pregnancy. In such instances, your provider will try to keep you and the baby healthy until you reach 37 weeks (which is when your baby has developed enough to be healthy outside of your womb) before inducing labor.

When early delivery isn’t an option or the condition occurs earlier in your pregnancy, the goal of treating preeclampsia is to reduce your blood pressure and avoid complications (like seizures and organ dysfunction) from occurring. To do this, your provider may recommend:

  • At-home blood pressure and fetal kick monitoring
  • Medications to maintain healthy blood pressure (e.g., calcium channel blockers)
  • Regular in-office appointments and ultrasounds to assess the growth of the baby and check the amniotic fluid (or, the fluid that surrounds the baby during pregnancy)

If preeclampsia is severe and you are not responding well to treatment, you may need to be admitted to the hospital for thorough observation and care until your provider is able to safely deliver your baby.


For the most part, there is no surefire way to prevent preeclampsia. However, getting regularly screened for preeclampsia and attending all of your appointments during your pregnancy can help catch preeclampsia early and get you started on treatment sooner—which can help reduce the risk of complications.

If you are at a higher risk of developing preeclampsia, your provider may advise you to take prophylactic treatments, such as low-dose aspirin (81 mg) or calcium supplements (1,000 mg) per day after you reach the 12-week mark of your pregnancy.


The majority of people with preeclampsia will go on to have normal, healthy births. This is especially the case if preeclampsia develops after 34 weeks of pregnancy or during the postpartum period. But, some earlier cases of preeclampsia can result in complications for the birthing parent and the baby. If your preeclampsia is left undiagnosed or untreated, you may face poor birth outcomes.

Complications for the Birthing Parent

If preeclampsia is left untreated, you may experience:

  • Liver or kidney failure
  • Pulmonary edema
  • Blood clots
  • Stroke or seizures
  • HELLP syndrome, which causes hemolysis, elevated liver enzymes, and a low platelet count

In severe cases, preeclampsia can be fatal. Unfortunately, from 2017 to 2019, the condition was responsible for about 6% of all pregnancy-related deaths.

Complications for the Baby

Severe preeclampsia can also affect the health of the baby during pregnancy and after their birth. Common complications affecting fetal outcomes include:

  • Intrauterine growth restriction: The baby doesn't grow to normal weight during pregnancy
  • Placental abruption: Separation of the placenta from the uterine wall before birth
  • Hypoxia: Low levels of oxygen
  • Premature birth: Delivering the baby before 37 weeks of pregnancy
  • Developmental conditions: Learning disorders or other intellectual disabilities

Unfortunately, preeclampsia can also cause infant death, with more than 10,000 infants per year in the U.S. dying from these complications. That said, it's especially important to attend all of your appointments and follow the treatment or monitoring plan that your healthcare provider recommends. If you are concerned about your symptoms and your provider is not taking your condition seriously, it's OK to talk to another provider that you trust for a second opinion.

Living With Preeclampsia  

If you receive a diagnosis for preeclampsia, it may be helpful to remember that it’s a temporary condition that typically resolves after childbirth. Birthing parents who develop the condition during pregnancy often recover within a few days to several weeks after delivering their baby. If you've developed the condition during postpartum (after childbirth), your blood pressure should go down within 12 weeks.

During your pregnancy, it's important to monitor your blood pressure and symptoms closely. It's also a good idea to talk to your healthcare provider about treatment options or lifestyle changes (e.g., stress management or certain diets) that you can incorporate to help reduce symptoms and prevent complications.

Frequently Asked Questions

  • What week does preeclampsia usually start?

    Preeclampsia can begin at any point during pregnancy, but it’s most common after 20 weeks of gestation. Most birthing parents develop preeclampsia in the third trimester, particularly between weeks 34 and 37. Preeclampsia can also start in the first six weeks after delivery.

  • How long can you carry a baby with preeclampsia?

    Healthcare providers usually advise you to carry a baby to around 37 weeks of gestation if you have preeclampsia. However, premature delivery before 37 weeks may be needed if there is any risk of complications for the birthing parent or baby. In general, babies delivered after 37 weeks aren’t at high risk for complications, and many people who develop preeclampsia late in pregnancy are induced before the baby has reached full term.

  • How long does preeclampsia last after delivery?

    Preeclampsia can resolve anywhere from 48 hours to a few weeks after childbirth.

  • Does preeclampsia affect the baby?

    The short answer: yes. Preeclampsia can inhibit your baby's growth and cause premature delivery or other pregnancy-related complications like placental abruption to occur.

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13 Sources
Health.com uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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