Eclampsia in Pregnancy: Warning Signs, Causes, Risk Factors and Treatment
Eclampsia is a life-threatening complication of pregnancy that causes seizures and requires immediate medical treatment. It is often associated with preeclampsia, a condition involving high blood pressure and possible damage to organs such as the brain, kidneys and liver. Recognizing warning signs, attending antenatal appointments and receiving timely obstetric care can help prevent serious complications.
This guide explains what eclampsia is, how it differs from preeclampsia, why it develops, who may be at increased risk and why early assessment matters. It is intended to help pregnant women, new mothers, families and caregivers understand this condition and make informed decisions about seeking care.
A seizure during pregnancy or after childbirth requires emergency medical assistance. If a pregnant woman or new mother develops a seizure, a severe persistent headache, changes in vision, severe pain beneath the ribs or difficulty breathing, seek urgent medical care immediately. Do not wait for a routine antenatal appointment or attempt to manage a seizure at home.
1. Understanding Eclampsia
Pregnancy brings changes in blood circulation, hormone levels, kidney function and metabolism. These adaptations help support the developing baby, but some pregnancies are complicated by conditions that threaten the health of both mother and child. Hypertensive disorders of pregnancy, particularly preeclampsia and eclampsia, are among the most important conditions to recognize early.
Preeclampsia usually develops after 20 weeks of pregnancy, although it can also first appear after delivery. It involves new-onset high blood pressure accompanied by protein in the urine or other evidence of organ dysfunction. Some affected women have few noticeable symptoms, which makes routine antenatal assessment especially important.
Eclampsia occurs when seizures develop in association with this pregnancy-related disorder and are not better explained by another cause. It can arise during pregnancy, labour or after childbirth. In some cases, a seizure is the first obvious indication that a serious hypertensive complication is present.
The condition is particularly dangerous because seizures can lead to injury, breathing difficulties, stroke and other severe complications. Prompt treatment can reduce these risks, which is why suspected eclampsia must be managed by trained healthcare professionals in an emergency setting.
2. The Global Burden of Preeclampsia and Eclampsia
Preeclampsia affects an estimated 3–8% of women who give birth worldwide, according to the World Health Organization (WHO). Some cases progress to eclampsia or other severe complications, including stroke, organ injury and premature delivery. Hypertensive disorders of pregnancy remain an important contributor to maternal and newborn illness and death.
The impact is not the same in every community. Access to antenatal appointments, blood pressure measurement, laboratory testing, emergency transport, essential medicines and skilled maternity services can influence how quickly complications are identified and treated.
In settings where travel to a health facility is difficult, delays in recognizing symptoms or reaching emergency obstetric care may have serious consequences. Improving access to timely assessment and treatment is therefore an important part of preventing avoidable harm.
Possible complications for the mother
- Stroke or bleeding in the brain: Severe hypertension and neurological complications can cause life-threatening brain injury.
- Kidney injury: Impaired kidney function can interfere with the body’s ability to regulate waste and fluids.
- Liver injury: Severe disease may cause liver abnormalities and upper abdominal pain.
- Pulmonary oedema: Fluid can accumulate in the lungs, making breathing difficult.
- HELLP syndrome: This serious complication involves haemolysis, elevated liver enzymes and a low platelet count.
- Blood-clotting problems: Severe illness can interfere with normal clotting and increase the risk of bleeding.
- Maternal death: Without timely treatment, severe complications can be fatal.
Possible complications for the baby
- Preterm birth when early delivery is necessary for safety.
- Restricted fetal growth because of impaired placental function.
- Low birth weight.
- Reduced oxygen supply or fetal distress.
- Complications related to prematurity, including breathing difficulties.
- Stillbirth in severe cases.
These outcomes are not inevitable. Appropriate monitoring, treatment of severe hypertension, seizure prevention when indicated and timely decisions about delivery can substantially reduce the risk of serious complications.
3. What Is Eclampsia?
Eclampsia is a serious obstetric emergency characterized by new-onset seizures associated with preeclampsia when another explanation is not more likely. The seizures commonly involve loss of consciousness, stiffening of the body and rhythmic jerking movements. Confusion or reduced awareness may follow.
The condition is closely associated with disturbances affecting the brain and blood vessels. However, it is not simply a seizure caused by a high blood pressure reading. The underlying pregnancy-related disease can affect several organ systems, and the neurological complications may develop unpredictably.
How is preeclampsia different?
Preeclampsia is diagnosed when new high blood pressure develops after 20 weeks of pregnancy and is accompanied by proteinuria or other qualifying signs of organ dysfunction. Protein in the urine is not essential in every case. Depending on the clinical findings, complications may involve the kidneys, liver, blood platelets, lungs or nervous system.
Eclampsia refers specifically to seizures associated with the pregnancy-related condition. A woman does not need to have a previously confirmed diagnosis of preeclampsia for eclampsia to be suspected. Other causes of seizures, including epilepsy, stroke and certain metabolic disorders, must also be considered by the treating team.
When can eclampsia occur?
Eclampsia can occur before birth, during labour or after delivery. Although many cases occur during pregnancy or around childbirth, postpartum eclampsia may develop after a woman has left the maternity facility.
Delivery does not immediately eliminate all risk. Blood pressure and other complications may persist or worsen after birth, so women with preeclampsia need a clear follow-up plan and must know which symptoms require urgent reassessment.
4. Preeclampsia Versus Eclampsia: Key Differences
The two conditions are closely related, but they describe different clinical situations. Preeclampsia involves hypertension and associated evidence of disease; eclampsia involves seizures in the context of that disease.
| Feature | Preeclampsia | Eclampsia |
|---|---|---|
| Definition | Pregnancy-related hypertension with proteinuria or other qualifying organ dysfunction. | Seizures associated with preeclampsia that are not better explained by another cause. |
| Blood pressure | Elevated blood pressure is part of the diagnosis. | Hypertension is often present, but a previously documented high reading may be absent. |
| Protein in urine | May be present; it is not required in every case. | May be present or absent. |
| Neurological features | Headache, visual disturbances or other neurological symptoms may occur. | Seizures are the defining feature. |
| Urgency | Requires assessment and management based on severity. | Requires immediate emergency treatment. |
Neither condition should be assessed from symptoms alone. Healthcare professionals use blood pressure measurements, examination findings, blood and urine tests, and fetal assessment when appropriate to determine the severity of the disease and the safest treatment.
5. Normal Changes During Pregnancy
Understanding the normal physiology of pregnancy helps explain why disorders affecting the placenta and blood vessels can have consequences throughout the body.
During pregnancy, blood volume increases, the heart pumps more blood and circulation adapts to supply the uterus and placenta. Blood vessels normally become more responsive to hormonal signals, helping maintain adequate blood flow to maternal organs and the developing baby.
Kidney filtration also increases, changing how the body handles fluids and waste products. Hormonal and metabolic adaptations support fetal growth, while changes in the respiratory system help meet increased oxygen requirements.
These are normal physiological adaptations, not signs of preeclampsia in themselves. The problem arises when the processes regulating placental development, blood vessel function and maternal blood pressure become disrupted.
This distinction is important because symptoms such as swelling can occur in uncomplicated pregnancies as well as in serious medical conditions. New, sudden, severe or persistent symptoms should be assessed in context rather than automatically dismissed as normal pregnancy changes.
6. The Placenta and Its Role in Pregnancy
The placenta is a temporary organ that connects the developing baby to the mother’s circulation. It supports the transfer of oxygen and nutrients, removes fetal waste products and produces hormones that help maintain pregnancy.
Early in pregnancy, specialized placental cells called trophoblasts interact with the lining of the uterus. They help remodel maternal spiral arteries so that these vessels can supply blood to the placenta efficiently as the baby grows.
In a healthy pregnancy, this process creates a low-resistance blood supply that supports the placenta’s increasing needs. When placental development or blood flow is abnormal, the placenta may become stressed and release substances that affect the mother’s blood vessels.
Abnormal placental development is an important part of current explanations for preeclampsia, but it is not the only factor. Maternal health, immune responses, genetics and existing blood vessel conditions may also contribute. Researchers continue to investigate why the disease develops in some pregnancies and not others.
7. How Preeclampsia Develops
Preeclampsia is a complex disorder rather than a simple consequence of high blood pressure. In many cases, the process begins with abnormalities in placental development or function. The resulting changes can affect the mother’s blood vessels and the regulation of circulation throughout the body.
Placental stress and blood vessel dysfunction
When placental blood flow is inadequate or the placenta is under stress, it can release biological signals that alter the function of the maternal vascular endothelium—the thin layer of cells lining blood vessels.
These changes can interfere with the normal balance between substances that relax blood vessels and those that cause them to constrict. Blood pressure may rise, and the circulation may become less effective at meeting the needs of organs and tissues.
Effects on the mother’s organs
The resulting vascular dysfunction can affect more than blood pressure. The kidneys may become less effective at filtering blood, and protein may leak into the urine. Liver injury can produce abnormal blood test results or pain in the upper abdomen. Platelet counts may fall, and fluid may accumulate in the lungs.
The brain is also vulnerable. Disturbances in blood vessel regulation and cerebral function can contribute to severe headaches, visual symptoms and, in some cases, seizures. When seizures occur in association with preeclampsia, eclampsia must be considered and treated as an emergency.
Eclampsia cannot be predicted reliably from a single symptom or blood pressure reading. Some women develop severe complications with limited warning. Regular antenatal assessment and urgent evaluation of concerning symptoms remain essential, even when a woman previously felt well.
8. Why Early Recognition Matters
Early recognition gives healthcare professionals an opportunity to identify worsening disease and act before serious complications occur. Antenatal appointments allow blood pressure to be checked, symptoms to be reviewed and additional investigations to be arranged when necessary.
Depending on the clinical situation, management may include medication to lower dangerously high blood pressure, magnesium sulfate to prevent or treat seizures, laboratory monitoring and assessment of the baby’s wellbeing. The timing of delivery is determined by the mother’s condition, the baby’s condition, gestational age and the available monitoring and treatment options.
Delivery is the definitive way to end the pregnancy-related placental process, but it does not mean that every complication resolves immediately. Continued observation and postpartum follow-up may be necessary because hypertension and other serious features can persist or develop after birth.
Warning signs that need urgent medical assessment
- A severe or persistent headache, particularly one that does not improve.
- Blurred vision, flashing lights, spots or other new visual disturbances.
- Severe pain beneath the ribs or in the upper abdomen.
- Sudden or marked swelling of the face or hands, especially when accompanied by other symptoms.
- New difficulty breathing or sudden shortness of breath.
- Confusion, collapse or a seizure.
These symptoms do not all indicate preeclampsia, but they can signal serious illness and should not be ignored during pregnancy or after childbirth. A seizure or severe breathing difficulty requires emergency assistance.
What families and caregivers can do
Partners, relatives and caregivers can help by supporting attendance at antenatal appointments, learning the warning signs and arranging prompt transport to a health facility when symptoms develop. If a woman has a seizure, protect her from nearby hazards, do not restrain her movements, place nothing in her mouth and seek emergency assistance immediately. If possible, turn her onto her side when this can be done safely, and remain with her while help is arranged.
Do not give food, drink or oral medicines to someone who is unconscious or actively having a seizure. Even if the seizure stops and she appears to recover, urgent medical evaluation is still necessary.
9. Risk Factors for Preeclampsia and Eclampsia
Eclampsia can affect women with different pregnancy histories and health backgrounds. Certain characteristics are associated with a higher likelihood of developing preeclampsia, which can progress to eclampsia. Having a risk factor does not mean that a woman will develop the condition, and women without recognized risk factors can still be affected.
Risk assessment helps healthcare professionals decide whether closer monitoring, specialist review or preventive treatment may be appropriate. The assessment should be individualized rather than based on one characteristic alone.
1. First pregnancy
Preeclampsia is more common in a first pregnancy than in some subsequent pregnancies. The biological reasons are complex and are thought to involve interactions between maternal adaptation, placental development and immune responses. Most first pregnancies do not develop preeclampsia, but this history is relevant during antenatal risk assessment.
2. Previous preeclampsia or eclampsia
A previous pregnancy complicated by preeclampsia or eclampsia increases the likelihood of preeclampsia in a future pregnancy. The degree of risk depends on factors such as the severity of the earlier episode, how early it occurred and the presence of other medical conditions.
A previous history should be discussed during early antenatal care so that an appropriate monitoring and prevention plan can be developed.
3. Chronic hypertension
Women who have high blood pressure before pregnancy are at increased risk of developing preeclampsia during pregnancy. This is sometimes described as preeclampsia superimposed on chronic hypertension.
Blood pressure control and medication review before and during pregnancy are important. Some medicines used for hypertension outside pregnancy are not suitable during pregnancy, so treatment should be reviewed by a qualified healthcare professional. Prescribed medicines should not be stopped or changed without medical advice.
4. Kidney disease
Chronic kidney disease can increase the risk of hypertensive complications in pregnancy. Because kidney disease may also affect blood pressure and protein levels in urine, healthcare professionals may need to compare findings during pregnancy with the woman’s previous results.
5. Diabetes
Type 1 and type 2 diabetes are recognized risk factors for preeclampsia. Good pre-pregnancy planning, appropriate diabetes management and regular antenatal care can help healthcare professionals monitor maternal health and identify complications.
6. Multiple pregnancy
Women carrying twins, triplets or more than one baby have a higher risk of preeclampsia than women carrying a single fetus. Multiple pregnancies generally require antenatal monitoring tailored to the needs of both the mother and babies.
7. Autoimmune conditions
Certain autoimmune diseases, including systemic lupus erythematosus, are associated with an increased risk of preeclampsia. Women with these conditions may benefit from pre-pregnancy counselling and coordinated care involving obstetric and relevant specialist teams.
8. Other factors that may increase risk
Additional factors associated with preeclampsia include obesity, older maternal age, a family history of preeclampsia, a long interval between pregnancies and some previous adverse pregnancy outcomes. Risk is influenced by the combination of factors rather than any single characteristic in isolation.
Healthcare professionals use established guidance to determine whether preventive measures, such as prescribed low-dose aspirin, are appropriate. Aspirin should not be started independently during pregnancy; the decision, dose and timing should be discussed with a qualified clinician.
Risk factors help guide care, but they cannot reliably predict every case. Regular antenatal appointments remain important even when a woman feels healthy or has no known risk factors.
Medical References and Further Reading
The medical information in this article has been prepared with reference to established public-health guidance and professional clinical resources. Readers can consult the following sources for additional information.
- World Health Organization: Pre-eclampsia. Information on the burden, prevention and management of preeclampsia.
- WHO recommendations for prevention and treatment of pre-eclampsia and eclampsia. Clinical recommendations concerning magnesium sulfate and obstetric management.
- American College of Obstetricians and Gynecologists: Preeclampsia and High Blood Pressure During Pregnancy. Patient guidance on warning signs, risk factors and follow-up.
- National Institute for Health and Care Excellence: Hypertension in Pregnancy. Recommendations on assessment, management and postpartum monitoring.
Medical Disclaimer
This article is intended for general health education. It does not replace a clinical examination, diagnosis or individualized medical advice from a qualified healthcare professional. Eclampsia is a medical emergency. If a seizure or other severe warning sign occurs during pregnancy or after delivery, seek emergency medical care immediately.