Eclampsia

Eclampsia is a rare but serious pregnancy complication where a woman with high blood pressure suddenly experiences seizures. Though affecting fewer than 1% of pregnant women with high blood pressure, this medical emergency requires immediate treatment to protect both mother and baby.

Table of contents

• What Is Eclampsia?
• Related Conditions
• When Does Eclampsia Occur?
• What Causes Eclampsia?
• Signs and Symptoms
• Risk Factors
• Diagnosis
• Treatment
• Complications
• Outlook

What Is Eclampsia?

Eclampsia is a severe pregnancy complication characterized by the sudden onset of seizures in a pregnant or postpartum woman with preeclampsia, a condition marked by high blood pressure and protein in the urine^[1]. These seizures occur in the absence of other underlying causes such as epilepsy or cerebrovascular events^[2]. Eclampsia is a life-threatening medical emergency that can lead to injury or death of both the pregnant woman and her baby^[1].

The name “eclampsia” comes from the Greek word for “lightning,” chosen because the condition was historically observed to appear suddenly without warning signs^[3]. The condition has been recognized clinically for over 2,000 years, since the time of Hippocrates, when the Greek physician Celsus described pregnancy-associated seizures that disappeared after delivery of the baby^[3].

Eclampsia is rare in developed countries. In the United States, it affects between 1 and 10 pregnant women out of every 10,000, representing fewer than 1% of pregnant women with high blood pressure during pregnancy^[1]. Globally, eclampsia affects about 1.4% of deliveries^[7]. However, in developing countries, the condition can affect 10 to 30 times as many women due to differences in access to medical care^[7].

Related Conditions

Maternal Seizure Disorder

Preeclampsia

Eclampsia is closely related to preeclampsia, which is a hypertensive disorder of pregnancy. Preeclampsia typically occurs when a pregnant woman develops new-onset high blood pressure (a systolic pressure of 140 mm Hg or higher and/or a diastolic pressure of 90 mm Hg or higher) after 20 weeks of gestation, along with protein in the urine or other signs of organ damage^[4]. In healthy pregnant women, blood pressure levels remain normal throughout pregnancy and postpartum, but preeclampsia disrupts this pattern^[1].

Preeclampsia was originally identified as a disorder preceding eclampsia, which is why it carries the prefix “pre”^[3]. Eclamptic seizures usually occur as a later complication of severe preeclampsia, but they may also arise without any prior signs of severe disease^[3]. Most cases of eclampsia develop in women who have been diagnosed with preeclampsia, though in some cases, eclampsia may arise in a pregnant or postpartum woman not previously diagnosed with the condition^[1].

Because doctors cannot predict which patients with preeclampsia will advance to eclampsia, anticonvulsant (anti-seizure) medication may be given to pregnant and postpartum women with severe preeclampsia to reduce their risk of seizures^[1].

HELLP Syndrome

Gestational Hypertension

Hypertensive Disorders of Pregnancy

When Does Eclampsia Occur?

Eclampsia typically occurs during the final trimester of pregnancy, specifically between weeks 28 and 40, but it can arise any time after 20 weeks of pregnancy^[1]. The condition can even occur during labor and delivery^[1].

Most cases of eclamptic seizures occur during the antepartum period (50 to 70% of cases), approximately 20 to 30% occur during labor, and another 20 to 30% develop after delivery^[4]. The highest risk of occurrence is within the first 48 hours postpartum, though the condition can develop up to 6 weeks after delivery^[1][2]. Rare cases have been reported as late as 23 days postpartum^[4].

What Causes Eclampsia?

The exact cause of eclampsia is not known^[1]. Doctors aren’t sure what causes the condition, though it may be related to problems with the development of the placenta (the organ that links the baby’s blood supply to the mother’s) or poor blood flow to the placenta^[1].

Several factors have been proposed as potentially contributing to eclampsia, including genetic factors, inflammatory changes in the body, blood clotting abnormalities, brain inflammation, or hormone imbalances^[1]. Other proposed factors include immunologic abnormalities, placental ischemia or infarction, and endothelial cell dysfunction^[4].

The mechanisms responsible for the development of eclampsia remain unclear^[4]. Eclampsia typically develops from preeclampsia, and high blood pressure from preeclampsia puts pressure on blood vessels. There can be swelling in the brain, which may lead to seizures^[9].

Signs and Symptoms

The hallmark symptom of eclampsia is seizures^[1]. Pregnant or postpartum women may experience seizures that typically last 1 to 2 minutes^[1][7]. During the seizure, women typically experience facial twitching, have a series of rapid body-wide muscle contractions and relaxations, foam at the mouth, and become unconscious for a short period after the seizure^[1].

After the seizure ends, women may act confused or agitated after regaining consciousness, hyperventilate during seizure recovery, and have no memory of the seizure^[1]. Eclampsia manifests as one or more seizures followed by coma or a period of unconsciousness lasting for a variable duration, with altered mental status and no recollection of the event^[4].

Some women experience seizure-related complications, such as biting their tongues, hitting their heads on the floor (causing head trauma), and breaking bones due to falls^[1].

Warning Signs

Many people will have warning signs before having a seizure caused by eclampsia. Typically, eclamptic seizures are preceded by signs and symptoms such as severe persistent headache (in 66% of cases), visual disturbances (27%), and/or epigastric pain (25%)^[4].

Warning signs that should prompt immediate medical attention include^[1][9]:

• Severe headaches
• Blurred vision, seeing double, or loss of vision
• Abdominal pain, especially on the upper right side
• Nausea or vomiting
• Difficulty breathing
• Trouble urinating or not urinating often
• Swelling of the hands, face, or ankles

It is important to note that eclampsia can occur during pregnancy or the postpartum period, even without warning signs like high blood pressure^[3]. However, eclampsia is often accompanied by high blood pressure readings^[3].

Risk Factors

The biggest risk factor for eclampsia is preeclampsia^[9]. However, most people with preeclampsia don’t develop eclampsia. It affects less than 3% of people with preeclampsia^[9].

Pregnant women are at increased risk of eclampsia if they^[1][4][9]:

• Have never been pregnant before (nulliparity)
• Are pregnant with twins or other multiples (multifetal gestation)
• Have a personal or family history of preeclampsia or eclampsia
• Are teenagers (younger than 18) or age 35 or older
• Experienced fetal growth restriction or stillbirth in a previous pregnancy
• Had placental abruption (the placenta detaching from the uterus) in a previous pregnancy
• Have an autoimmune condition
• Have diabetes, hypertension (high blood pressure), or kidney disease
• Consume a poor diet or have obesity (a BMI of 30 or greater)
• Are Black or Hispanic
• Have preterm delivery less than 32 weeks’ gestation
• Lack prenatal care
• Got pregnant through in-vitro fertilization

It’s important to note that women may develop eclampsia without having any of these risk factors^[9].

Diagnosis

Your healthcare provider diagnoses eclampsia based on the presence of a seizure in a pregnant or postpartum woman, particularly one with preeclampsia^[9]. It’s unlikely that you’ll notice early signs of preeclampsia yourself, but they should be picked up during your routine antenatal appointments^[6].

Your obstetrician will perform an exam, blood work, and regular blood pressure monitoring^[9]. They will also order urine tests to look for increased protein in the urine^[9].

Diagnostic tests may include^[5][9]:

• Blood tests: These may show abnormal factors like red blood cell count, platelet count, blood clotting factors, blood creatinine, hematocrit, uric acid, and liver function
• Urine tests: Urine tests typically show large amounts of protein in your urine
• Creatinine tests: Creatinine is a waste product that’s typically filtered out of your blood by your kidneys. Abnormally high levels of creatinine could be a sign of kidney failure

Your healthcare provider will also monitor the fetus and check its heart rate, movement, size, and other factors through ultrasound to ensure it’s tolerating pregnancy well^[9].

Treatment

Eclamptic convulsions are life-threatening emergencies and require proper treatment to decrease maternal morbidity and mortality^[11]. The main treatment to prevent severe preeclampsia from progressing to eclampsia is giving birth to the baby^[5]. Delivery is the only definitive treatment for eclampsia^[11].

The best treatment for eclampsia is giving birth. If the fetus is 37 weeks gestation or more, inducing labor or performing a cesarean section is recommended^[9]. In most cases of preeclampsia, having your baby at about the 37th to 38th week of pregnancy is recommended^[13]. If your condition becomes more severe before 37 weeks and there are serious concerns about the health of you or your baby, earlier delivery may be necessary^[13].

Medication

Magnesium sulfate (given intravenously or intramuscularly) is the treatment of choice for severe preeclampsia to prevent eclampsia, or after eclampsia develops to prevent more seizures^[3][11]. The use of magnesium sulfate improves outcomes in those with severe preeclampsia and eclampsia and is generally safe^[7].

Magnesium treatment is generally continued for 24 to 48 hours after the last seizure or beyond delivery^[3]. You may receive magnesium sulfate in an intensive care unit or a labor and delivery unit. While magnesium is given, you will be observed closely, receive intravenous fluids, and may have a catheter placed in your bladder to measure urine output^[3].

You may be given medicine to lower high blood pressure. Treatment options include blood pressure medications such as hydralazine, labetalol, or nifedipine^[7][11]. You’ll be offered medicine to lower your blood pressure while you wait for your baby to be delivered^[13].

Supportive Care

Supportive care for eclamptic convulsions includes close monitoring (invasive, if clinically indicated), airway support, adequate oxygenation, anticonvulsant therapy, and blood pressure control^[11].

The patient should be placed in the left lateral position to decrease the risk of aspiration and help improve uterine blood flow by relieving obstruction of the vena cava by the gravid uterus^[11]. Healthcare providers should protect the patient against injury during the seizure by padding and raising guardrails, using a padded tongue blade between the teeth, and suctioning oral secretions as needed^[11].

After Delivery

Although preeclampsia usually improves soon after your baby is born, complications can sometimes develop a few days later^[13]. You may need to stay in hospital after the birth so you can be monitored. Your blood pressure will be measured regularly, and you may be offered medicine if it gets too high^[13].

Complications

Eclampsia is a major cause of maternal mortality in the United States and worldwide^[14]. If preeclampsia is not treated, it can cause serious problems, such as preterm birth and even death^[22]. Complications, which may lead to injury or death of the mother and/or baby, occur in 5.6% to 14% of women with eclampsia, highlighting the importance of proper diagnosis and treatment^[1].

Seizures can lead to dangerous complications, including difficulty breathing, blood clots, stroke, coma, heart failure, premature birth, and maternal and fetal death^[1]. Maternal mortality due to eclampsia occurs at a rate of approximately 0 to 1.8% of cases in high-income countries and up to 15% of cases in low- to middle-income countries^[7].

Seizures can lead to severe complications like maternal hypoxia, trauma, and aspiration pneumonia^[2]. Pregnant women may develop pulmonary edema, acute kidney injury, liver rupture, or cerebral hemorrhage, with or without seizures^[4].

Women who have preeclampsia are at risk of placental abruption in the current pregnancy, possibly because both disorders are related to uteroplacental insufficiency^[14]. Fetal complications may include growth restriction, oligohydramnios, or stillbirth^[14].

Long-term neurological damage is rare. However, some women may experience lasting cognitive impairments, particularly after recurrent seizures or untreated severe hypertension^[2].

Outlook

Most pregnant people who have preeclampsia have healthy babies^[22]. Most women will have healthy babies and improve soon after the condition typically begins to resolve after childbirth^[1][13]. Importantly, treatments for eclampsia are available to help stop seizures, safely lower blood pressure, and deliver the baby safely^[1].

In the developed world, eclampsia is rare and usually treatable if appropriate intervention is promptly sought^[3]. Left untreated, eclamptic seizures can result in coma, brain damage, and possibly maternal or infant death^[3].

You can have preeclampsia and not know it, so it’s essential to go to all of your prenatal care visits, even if you’re feeling fine^[22]. The earlier preeclampsia is diagnosed and monitored, the better the outlook for mother and baby^[6]. Early diagnosis and transport to the appropriate level of maternal care are mandatory after initial stabilization^[11].