Preeclampsia is a condition that causes a sudden rise in blood pressure during pregnancy. It can also lead to clotting issues that may affect organs, such as the liver and kidneys.

Preeclampsia is the most common complication to occur during pregnancy. It generally develops during the third trimester and affects about 1 in 25 pregnancies.

It can progress into eclampsia in some people, where they can experience seizures and enter a coma. It can also be fatal. Prenatal appointments are an important component of managing health, preeclampsia, and potential conditions such as eclampsia.

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Preeclampsia may present no initial symptoms, but common signs include:

  • protein in the urine
  • high blood pressure
  • blurry vision, sometimes seeing flashing lights
  • headaches, often severe
  • feeling ill
  • shortness of breath
  • pain just below the ribs on the right side
  • rapid weight gain, caused by excess fluid
  • nausea and vomiting during the second half of pregnancy
  • urinating less often
  • lower platelet count
  • impaired liver function

Pregnant people should seek immediate medical attention if they experience any of these signs or symptoms.

Although some people may develop high blood pressure during pregnancy, it does not necessarily mean they have preeclampsia. The criteria for diagnosing preeclampsia include elevated blood pressure and at least one correlating sign from above.

As preeclampsia progresses, people may experience fluid retention, with swelling in the hands, feet, ankles, and face.

Swelling, or edema, can be a common part of pregnancy, especially during the third trimester. It tends to occur in the lower parts of the body, such as the ankles and feet. Symptoms are typically milder first thing in the morning and build up during the day. This is not preeclampsia, in which edema occurs suddenly and tends to be much more severe.

Preeclampsia can also restrict the baby’s growth because of decreased blood supply to the placenta.

Experts are not sure why preeclampsia occurs. Most say there is a problem with the placenta’s development because the blood vessels that supply it respond differently to hormonal signals and are narrower than normal, limiting blood flow.

Experts also do not fully understand why the blood vessels develop differently, but several factors may play a role. These include:

  • damage to the blood vessels
  • insufficient blood flow to the uterus
  • immune system problems
  • genetic factors

Preeclampsia is not cured until the baby is delivered.

Until the pregnant person’s blood pressure reduces, they are at a greater risk of stroke, severe bleeding, separation of the placenta from the uterus, and seizures. In some cases, especially if preeclampsia develops earlier in pregnancy, early delivery may not be the best option for the baby.

People who have had preeclampsia in previous pregnancies are advised to attend prenatal visits more often. The doctor may recommend the following medications:

  • Antihypertensives: These help to lower blood pressure.
  • Anticonvulsants: In severe cases, doctors may use these drugs to prevent a first seizure. They may prescribe magnesium sulfate.
  • Corticosteroids: If the person has preeclampsia or HELLP syndrome – see below – these drugs can help induce fetal lung maturity to prepare for premature delivery. This can prolong the pregnancy.

Rest

If the person is far from the end of their pregnancy and has mild symptoms, the doctor may advise bed rest. Resting helps bring the blood pressure down, increasing blood flow to the placenta and benefiting the baby.

Doctors may advise some people to lie down in bed and only sit up or stand when needed. Others may be allowed to sit in an armchair or on the sofa or bed, but their physical activities will be strictly limited. There will be regular blood pressure and urine tests, and doctors will also monitor the baby closely.

In severe cases, the pregnant person may be hospitalized for continuous bed rest and monitored closely.

Inducing labor

With a diagnosis of preeclampsia close to the end of pregnancy, doctors may advise delivering the baby early.

There may be no choice in very severe cases, and doctors will induce the labor or perform a cesarean delivery as soon as possible. The doctor may give the parent magnesium sulfate to improve uterine blood flow and prevent seizures during childbirth.

Symptoms of preeclampsia should go away within a few weeks of delivery.

For a doctor to diagnose preeclampsia, the pregnant person must have a diagnosis of high blood pressure and at least one additional associated sign, such as decreased blood platelets or impaired liver function.

Hypertension

This is the term for high blood pressure. A blood pressure reading of 140/90 mm Hg or higher is abnormal in pregnancy.

The doctor may also order diagnostic tests:

  • Blood tests: This checks kidney and liver function and whether the blood is clotting properly.
  • Fetal ultrasound: Doctors will closely monitor the baby’s progress to make sure they are growing properly.
  • Non-stress test: The doctor checks how the baby’s heartbeat reacts when they move. If the heartbeat increases 15 beats or more a minute for at least 15 seconds twice every 20 minutes, it is an indication that everything is normal.

Risk factors associated with preeclampsia include:

  • First pregnancies: The chances of preeclampsia during a first pregnancy are considerably higher than subsequent ones.
  • Family history: A person whose parent or sibling had preeclampsia has a higher risk of developing it.
  • Personal history of preeclampsia: A person who had preeclampsia in their first pregnancy can have a much greater risk of having the same condition in subsequent pregnancies.
  • Certain conditions and illnesses: People with diabetes, chronic high blood pressure, autoimmune conditions, and kidney disease are more likely to develop preeclampsia.
  • Obesity: Preeclampsia rates are much higher among obese people.
  • Multiple pregnancies: If a person is expecting two or more babies, the risk is higher.

While the prevalence of preeclampsia is 3–5%, its impact is not equal across all populations. The rates of occurrence and outcomes are disproportionate among groups such as non-Hispanic Black women and American Indian or Alaskan Native women.

Furthermore, most of the currently available data that examines disparities primarily compare the differences between non-Hispanic Black and white women.

Additionally, only a small number of studies examine outcomes for mixed-race, Asian, American Indian, or Alaskan Native women.

A 2017 report examined the prevalence of preeclampsia in 2014. It included data from nearly 177,000 deliveries in women with preeclampsia or eclampsia.

The total rates of preeclampsia and eclampsia based on race and ethnicity:

  • 69.8 per 1,000 deliveries for Black women
  • 46.8 per 1,000 deliveries for Hispanic women
  • 43.3 per 1,000 deliveries for white women
  • 28.8 per 1,000 deliveries for Asian/Pacific Islander women

However, studies discussing preeclampsia and using race and ethnic differences for clarity do not often consider contributing factors. Further research is warranted that considers behavioral, environmental, genetic, and socioeconomic factors as well as access to healthcare.

Preeclampsia is not fully preventable, but there are several steps a pregnant person can take to moderate some factors that contribute to high blood pressure.

These can include:

  • drinking between 6 and 8 glasses of water every day
  • avoiding fried or highly processed foods
  • excluding added salt
  • avoiding alcohol and caffeine
  • taking regular exercise under their doctor’s guidance
  • keeping feet elevated a few times per day
  • resting

These steps can help maintain healthy blood pressure and may reduce the risk of preeclampsia. Pregnant people should follow their doctor’s advice on diet and exercise.

In rare cases, a person may experience high blood pressure after giving birth. This is known as postpartum preeclampsia and can occur between a few days and a few weeks after delivery. The main symptoms are high blood pressure and protein in the urine. The typical accompanying symptoms of preeclampsia, such as severe headaches and a swollen face, can also occur.

Postpartum preeclampsia is easily treated with blood pressure medications that reduce and prevent seizures. Doctors will prescribe drugs that will not affect the ability to breastfeed.

There is a risk of serious complications with untreated preeclampsia. Complications may be prevented if the signs of preeclampsia are detected sooner, which is possible by attending routine prenatal visits. However, if the condition is not diagnosed for some reason, the risks are considerably greater.

The following complications may develop from preeclampsia:

Hemolysis, elevated liver enzymes, low platelet count (HELLP) syndrome: HELLP can very quickly become life threatening for both the pregnant person and the baby. It stands for hemolysis, elevated liver enzymes, and low platelet count. It is a combined liver and blood clotting disorder that most commonly occurs right after giving birth but can appear at any time after the 20th week of pregnancy. Very rarely, it may occur beforehand. The only way to treat HELLP syndrome effectively is to deliver the baby as soon as possible.

Poor blood flow to the placenta: If blood flow to the placenta is restricted, the baby might not be getting oxygen and nutrients, which may lead to slower growth, breathing difficulties, and premature birth.

Placental abruption: The placenta separates from the inner wall of the uterus. In severe cases, there may be heavy bleeding, which can damage the placenta. Any damage to the placenta may place the baby’s and pregnant person’s life at risk.

Eclampsia: This is a combination of preeclampsia and seizures. The pregnant person may experience pain under the ribs on the right side of their body, intense headache, blurry vision, confusion, and decreased alertness. If left untreated, they are at risk of coma, permanent brain damage, and death. The condition is also life threatening for the baby.

Preeclampsia can have some long-term consequences for the developing baby. Research shows that high blood pressure in pregnant people may affect the baby’s cognitive skills, which can carry through into later life.

Preeclampsia is a complication of pregnancy where there is a sudden rise in blood pressure. It usually develops during the third trimester.

Preeclampsia is not entirely preventable, but visiting a doctor for regular prenatal visits may lead to early detection. Limiting highly processed foods and choosing fruits and vegetables — frozen and canned are great options — can also help to keep people and their babies healthier during pregnancy.

It is advisable for pregnant people to speak with a healthcare professional about their risk of developing preeclampsia and its warning signs.